Merge "Implement resize enter animation" into udc-dev am: 460be670c7

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/22881925

Change-Id: I0b469ff94c4d56cef5988ce834bc6992a983dfaa
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>

libs/WindowManager/Shell/src/com/android/wm/shell/common/split/SplitDecorManager.java

@@ -22,6 +22,8 @@ import static android.view.WindowManager.LayoutParams.PRIVATE_FLAG_NO_MOVE_ANIMA
 import static android.view.WindowManager.LayoutParams.PRIVATE_FLAG_TRUSTED_OVERLAY;
 import static android.view.WindowManager.LayoutParams.TYPE_APPLICATION_OVERLAY;
 
+import static com.android.wm.shell.common.split.SplitScreenConstants.FADE_DURATION;
+
 import android.animation.Animator;
 import android.animation.AnimatorListenerAdapter;
 import android.animation.ValueAnimator;
@@ -60,7 +62,6 @@ public class SplitDecorManager extends WindowlessWindowManager {
     private static final String TAG = SplitDecorManager.class.getSimpleName();
     private static final String RESIZING_BACKGROUND_SURFACE_NAME = "ResizingBackground";
     private static final String GAP_BACKGROUND_SURFACE_NAME = "GapBackground";
-    private static final long FADE_DURATION = 133;
 
     private final IconProvider mIconProvider;
     private final SurfaceSession mSurfaceSession;
@@ -263,6 +264,7 @@ public class SplitDecorManager extends WindowlessWindowManager {
 
             final SurfaceControl.Transaction animT = new SurfaceControl.Transaction();
             mScreenshotAnimator = ValueAnimator.ofFloat(1, 0);
+            mScreenshotAnimator.setDuration(FADE_DURATION);
             mScreenshotAnimator.addUpdateListener(valueAnimator -> {
                 final float progress = (float) valueAnimator.getAnimatedValue();
                 animT.setAlpha(mScreenshot, progress);

libs/WindowManager/Shell/src/com/android/wm/shell/common/split/SplitScreenConstants.java

@@ -43,6 +43,11 @@ public class SplitScreenConstants {
      */
     public static final int SPLIT_POSITION_BOTTOM_OR_RIGHT = 1;
 
+    /**
+     * Duration used for every split fade-in or fade-out.
+     */
+    public static final int FADE_DURATION = 133;
+
     @IntDef(prefix = {"SPLIT_POSITION_"}, value = {
             SPLIT_POSITION_UNDEFINED,
             SPLIT_POSITION_TOP_OR_LEFT,

libs/WindowManager/Shell/src/com/android/wm/shell/splitscreen/SplitScreenTransitions.java

@@ -22,6 +22,7 @@ import static android.view.WindowManager.TRANSIT_OPEN;
 import static android.view.WindowManager.TRANSIT_TO_BACK;
 import static android.view.WindowManager.TRANSIT_TO_FRONT;
 
+import static com.android.wm.shell.common.split.SplitScreenConstants.FADE_DURATION;
 import static com.android.wm.shell.common.split.SplitScreenConstants.FLAG_IS_DIVIDER_BAR;
 import static com.android.wm.shell.splitscreen.SplitScreen.stageTypeToString;
 import static com.android.wm.shell.splitscreen.SplitScreenController.EXIT_REASON_DRAG_DIVIDER;
@@ -34,7 +35,6 @@ import android.animation.AnimatorListenerAdapter;
 import android.animation.ValueAnimator;
 import android.annotation.NonNull;
 import android.annotation.Nullable;
-import android.graphics.Rect;
 import android.os.IBinder;
 import android.view.SurfaceControl;
 import android.view.WindowManager;
@@ -63,7 +63,7 @@ class SplitScreenTransitions {
     private final Runnable mOnFinish;
 
     DismissSession mPendingDismiss = null;
-    TransitSession mPendingEnter = null;
+    EnterSession mPendingEnter = null;
     TransitSession mPendingResize = null;
 
     private IBinder mAnimatingTransition = null;
@@ -120,6 +120,7 @@ class SplitScreenTransitions {
             @NonNull SurfaceControl.Transaction t, @NonNull WindowContainerToken mainRoot,
             @NonNull WindowContainerToken sideRoot, @NonNull WindowContainerToken topRoot) {
         // Play some place-holder fade animations
+        final boolean isEnter = isPendingEnter(transition);
         for (int i = info.getChanges().size() - 1; i >= 0; --i) {
             final TransitionInfo.Change change = info.getChanges().get(i);
             final SurfaceControl leash = change.getLeash();
@@ -142,17 +143,23 @@ class SplitScreenTransitions {
                             change.getEndRelOffset().x, change.getEndRelOffset().y);
                 }
             }
-            boolean isRootOrSplitSideRoot = change.getParent() == null
-                    || topRoot.equals(change.getParent());
-            boolean isDivider = change.getFlags() == FLAG_IS_DIVIDER_BAR;
-            // For enter or exit, we only want to animate side roots and the divider but not the
-            // top-root.
-            if (!isRootOrSplitSideRoot || topRoot.equals(change.getContainer()) || isDivider) {
-                continue;
-            }
 
-            if (isPendingEnter(transition) && (mainRoot.equals(change.getContainer())
+            final boolean isTopRoot = topRoot.equals(change.getContainer());
-                    || sideRoot.equals(change.getContainer()))) {
+            final boolean isMainRoot = mainRoot.equals(change.getContainer());
+            final boolean isSideRoot = sideRoot.equals(change.getContainer());
+            final boolean isDivider = change.getFlags() == FLAG_IS_DIVIDER_BAR;
+            final boolean isMainChild = mainRoot.equals(change.getParent());
+            final boolean isSideChild = sideRoot.equals(change.getParent());
+            if (isEnter && (isMainChild || isSideChild)) {
+                // Reset child tasks bounds on finish.
+                mFinishTransaction.setPosition(leash,
+                        change.getEndRelOffset().x, change.getEndRelOffset().y);
+                mFinishTransaction.setCrop(leash, null);
+            } else if (isEnter && isTopRoot) {
+                // Ensure top root is visible at start.
+                t.setAlpha(leash, 1.f);
+                t.show(leash);
+            } else if (isEnter && isMainRoot || isSideRoot) {
                 t.setPosition(leash, change.getEndAbsBounds().left, change.getEndAbsBounds().top);
                 t.setWindowCrop(leash, change.getEndAbsBounds().width(),
                         change.getEndAbsBounds().height());
@@ -161,10 +168,24 @@ class SplitScreenTransitions {
                 t.setLayer(leash, Integer.MAX_VALUE);
                 t.show(leash);
             }
+            // These container changes we don't want to animate them.
+            // We should only animate stage root, divider and child tasks are not under stage root.
+            if (isTopRoot || isMainChild || isSideChild || change.getTaskInfo() == null) {
+                continue;
+            }
+
+            if (isEnter && mPendingEnter.mResizeAnim) {
+                // We will run animation in next transition so skip anim here
+                continue;
+            } else if (isEnter && isMainRoot) {
+                // Main stage already on top so skip fade in animation to reduce flicker.
+                continue;
+            }
+
             boolean isOpening = TransitionUtil.isOpeningType(info.getType());
             if (isOpening && (mode == TRANSIT_OPEN || mode == TRANSIT_TO_FRONT)) {
                 // fade in
-                startExampleAnimation(leash, true /* show */);
+                startFadeAnimation(leash, true /* show */);
             } else if (!isOpening && (mode == TRANSIT_CLOSE || mode == TRANSIT_TO_BACK)) {
                 // fade out
                 if (info.getType() == TRANSIT_SPLIT_DISMISS_SNAP) {
@@ -173,7 +194,7 @@ class SplitScreenTransitions {
                     // and don't animate it so it doesn't pop-in when reparented.
                     t.setAlpha(leash, 0.f);
                 } else {
-                    startExampleAnimation(leash, false /* show */);
+                    startFadeAnimation(leash, false /* show */);
                 }
             }
         }
@@ -267,7 +288,7 @@ class SplitScreenTransitions {
             Transitions.TransitionHandler handler,
             @Nullable TransitionConsumedCallback consumedCallback,
             @Nullable TransitionFinishedCallback finishedCallback,
-            int extraTransitType) {
+            int extraTransitType, boolean resizeAnim) {
         if (mPendingEnter != null) {
             ProtoLog.v(ShellProtoLogGroup.WM_SHELL_TRANSITIONS, "  splitTransition "
                     + " skip to start enter split transition since it already exist. ");
@@ -275,7 +296,7 @@ class SplitScreenTransitions {
         }
         final IBinder transition = mTransitions.startTransition(transitType, wct, handler);
         setEnterTransition(transition, remoteTransition, consumedCallback, finishedCallback,
-                extraTransitType);
+                extraTransitType, resizeAnim);
         return transition;
     }
 
@@ -284,9 +305,10 @@ class SplitScreenTransitions {
             @Nullable RemoteTransition remoteTransition,
             @Nullable TransitionConsumedCallback consumedCallback,
             @Nullable TransitionFinishedCallback finishedCallback,
-            int extraTransitType) {
+            int extraTransitType, boolean resizeAnim) {
-        mPendingEnter = new TransitSession(
+        mPendingEnter = new EnterSession(
-                transition, consumedCallback, finishedCallback, remoteTransition, extraTransitType);
+                transition, consumedCallback, finishedCallback, remoteTransition, extraTransitType,
+                resizeAnim);
 
         ProtoLog.v(ShellProtoLogGroup.WM_SHELL_TRANSITIONS, "  splitTransition "
                 + " deduced Enter split screen");
@@ -409,78 +431,27 @@ class SplitScreenTransitions {
         }
     }
 
-    // TODO(shell-transitions): real animations
+    private void startFadeAnimation(@NonNull SurfaceControl leash, boolean show) {
-    private void startExampleAnimation(@NonNull SurfaceControl leash, boolean show) {
         final float end = show ? 1.f : 0.f;
         final float start = 1.f - end;
         final SurfaceControl.Transaction transaction = mTransactionPool.acquire();
         final ValueAnimator va = ValueAnimator.ofFloat(start, end);
-        va.setDuration(500);
+        va.setDuration(FADE_DURATION);
         va.addUpdateListener(animation -> {
             float fraction = animation.getAnimatedFraction();
             transaction.setAlpha(leash, start * (1.f - fraction) + end * fraction);
             transaction.apply();
         });
-        final Runnable finisher = () -> {
-            transaction.setAlpha(leash, end);
-            transaction.apply();
-            mTransactionPool.release(transaction);
-            mTransitions.getMainExecutor().execute(() -> {
-                mAnimations.remove(va);
-                onFinish(null /* wct */, null /* wctCB */);
-            });
-        };
         va.addListener(new AnimatorListenerAdapter() {
             @Override
             public void onAnimationEnd(Animator animation) {
-                finisher.run();
+                transaction.setAlpha(leash, end);
-            }
+                transaction.apply();
-
+                mTransactionPool.release(transaction);
-            @Override
+                mTransitions.getMainExecutor().execute(() -> {
-            public void onAnimationCancel(Animator animation) {
+                    mAnimations.remove(va);
-                finisher.run();
+                    onFinish(null /* wct */, null /* wctCB */);
-            }
+                });
-        });
-        mAnimations.add(va);
-        mTransitions.getAnimExecutor().execute(va::start);
-    }
-
-    // TODO(shell-transitions): real animations
-    private void startExampleResizeAnimation(@NonNull SurfaceControl leash,
-            @NonNull Rect startBounds, @NonNull Rect endBounds) {
-        final SurfaceControl.Transaction transaction = mTransactionPool.acquire();
-        final ValueAnimator va = ValueAnimator.ofFloat(0.f, 1.f);
-        va.setDuration(500);
-        va.addUpdateListener(animation -> {
-            float fraction = animation.getAnimatedFraction();
-            transaction.setWindowCrop(leash,
-                    (int) (startBounds.width() * (1.f - fraction) + endBounds.width() * fraction),
-                    (int) (startBounds.height() * (1.f - fraction)
-                            + endBounds.height() * fraction));
-            transaction.setPosition(leash,
-                    startBounds.left * (1.f - fraction) + endBounds.left * fraction,
-                    startBounds.top * (1.f - fraction) + endBounds.top * fraction);
-            transaction.apply();
-        });
-        final Runnable finisher = () -> {
-            transaction.setWindowCrop(leash, 0, 0);
-            transaction.setPosition(leash, endBounds.left, endBounds.top);
-            transaction.apply();
-            mTransactionPool.release(transaction);
-            mTransitions.getMainExecutor().execute(() -> {
-                mAnimations.remove(va);
-                onFinish(null /* wct */, null /* wctCB */);
-            });
-        };
-        va.addListener(new AnimatorListenerAdapter() {
-            @Override
-            public void onAnimationEnd(Animator animation) {
-                finisher.run();
-            }
-
-            @Override
-            public void onAnimationCancel(Animator animation) {
-                finisher.run();
             }
         });
         mAnimations.add(va);
@@ -569,6 +540,21 @@ class SplitScreenTransitions {
         }
     }
 
+    /** Bundled information of enter transition. */
+    class EnterSession extends TransitSession {
+        final boolean mResizeAnim;
+
+        EnterSession(IBinder transition,
+                @Nullable TransitionConsumedCallback consumedCallback,
+                @Nullable TransitionFinishedCallback finishedCallback,
+                @Nullable RemoteTransition remoteTransition,
+                int extraTransitType, boolean resizeAnim) {
+            super(transition, consumedCallback, finishedCallback, remoteTransition,
+                    extraTransitType);
+            this.mResizeAnim = resizeAnim;
+        }
+    }
+
     /** Bundled information of dismiss transition. */
     class DismissSession extends TransitSession {
         final int mReason;

libs/WindowManager/Shell/src/com/android/wm/shell/splitscreen/StageCoordinator.java

@@ -395,7 +395,8 @@ public class StageCoordinator implements SplitLayout.SplitLayoutHandler,
             mSplitTransitions.startEnterTransition(TRANSIT_TO_FRONT, wct,
                     null, this, null /* consumedCallback */, null /* finishedCallback */,
                     isSplitScreenVisible()
-                            ? TRANSIT_SPLIT_SCREEN_OPEN_TO_SIDE : TRANSIT_SPLIT_SCREEN_PAIR_OPEN);
+                            ? TRANSIT_SPLIT_SCREEN_OPEN_TO_SIDE : TRANSIT_SPLIT_SCREEN_PAIR_OPEN,
+                    !mIsDropEntering);
         } else {
             mSyncQueue.queue(wct);
             mSyncQueue.runInSync(t -> {
@@ -503,7 +504,8 @@ public class StageCoordinator implements SplitLayout.SplitLayoutHandler,
         prepareEnterSplitScreen(wct, null /* taskInfo */, position);
 
         mSplitTransitions.startEnterTransition(TRANSIT_TO_FRONT, wct, null, this,
-                null /* consumedCallback */, null /* finishedCallback */, extraTransitType);
+                null /* consumedCallback */, null /* finishedCallback */, extraTransitType,
+                !mIsDropEntering);
     }
 
     /** Launches an activity into split by legacy transition. */
@@ -661,7 +663,7 @@ public class StageCoordinator implements SplitLayout.SplitLayoutHandler,
 
         mSplitTransitions.startEnterTransition(
                 TRANSIT_TO_FRONT, wct, remoteTransition, this, null, null,
-                TRANSIT_SPLIT_SCREEN_PAIR_OPEN);
+                TRANSIT_SPLIT_SCREEN_PAIR_OPEN, false);
         setEnterInstanceId(instanceId);
     }
 
@@ -713,7 +715,7 @@ public class StageCoordinator implements SplitLayout.SplitLayoutHandler,
 
         mSplitTransitions.startEnterTransition(
                 TRANSIT_TO_FRONT, wct, remoteTransition, this, null, null,
-                TRANSIT_SPLIT_SCREEN_PAIR_OPEN);
+                TRANSIT_SPLIT_SCREEN_PAIR_OPEN, false);
         setEnterInstanceId(instanceId);
     }
 
@@ -1494,14 +1496,6 @@ public class StageCoordinator implements SplitLayout.SplitLayoutHandler,
 
     private void prepareBringSplit(WindowContainerTransaction wct,
             @Nullable ActivityManager.RunningTaskInfo taskInfo, @SplitPosition int startPosition) {
-        StageTaskListener targetStage;
-        if (isSplitScreenVisible()) {
-            // If the split screen is foreground, retrieves target stage based on position.
-            targetStage = startPosition == mSideStagePosition ? mSideStage : mMainStage;
-        } else {
-            targetStage = mSideStage;
-        }
-
         if (taskInfo != null) {
             wct.startTask(taskInfo.taskId,
                     resolveStartStage(STAGE_TYPE_UNDEFINED, startPosition, null, wct));
@@ -1510,13 +1504,8 @@ public class StageCoordinator implements SplitLayout.SplitLayoutHandler,
         // and evict all tasks current under its.
         if (!isSplitScreenVisible()) {
             // Recreate so we need to reset position rather than keep position of background split.
-            mSplitLayout.resetDividerPosition();
+            mMainStage.reparentTopTask(wct);
-            updateWindowBounds(mSplitLayout, wct);
+            prepareSplitLayout(wct);
-            final StageTaskListener anotherStage = targetStage == mMainStage
-                    ? mSideStage : mMainStage;
-            anotherStage.reparentTopTask(wct);
-            wct.reorder(mRootTaskInfo.token, true);
-            setRootForceTranslucent(false, wct);
         }
     }
 
@@ -1532,8 +1521,22 @@ public class StageCoordinator implements SplitLayout.SplitLayoutHandler,
             mSideStage.addTask(taskInfo, wct);
         }
         mMainStage.activate(wct, true /* includingTopTask */);
-        mSplitLayout.resetDividerPosition();
+        prepareSplitLayout(wct);
+    }
+
+    private void prepareSplitLayout(WindowContainerTransaction wct) {
+        if (mIsDropEntering) {
+            mSplitLayout.resetDividerPosition();
+        } else {
+            mSplitLayout.setDividerAtBorder(mSideStagePosition == SPLIT_POSITION_TOP_OR_LEFT);
+        }
         updateWindowBounds(mSplitLayout, wct);
+        if (!mIsDropEntering) {
+            // Reset its smallest width dp to avoid is change layout before it actually resized to
+            // split bounds.
+            wct.setSmallestScreenWidthDp(mMainStage.mRootTaskInfo.token,
+                    SMALLEST_SCREEN_WIDTH_DP_UNDEFINED);
+        }
         wct.reorder(mRootTaskInfo.token, true);
         setRootForceTranslucent(false, wct);
     }
@@ -1548,6 +1551,7 @@ public class StageCoordinator implements SplitLayout.SplitLayoutHandler,
         updateSurfaceBounds(mSplitLayout, t, false /* applyResizingOffset */);
         t.show(mRootTaskLeash);
         setSplitsVisible(true);
+        mIsDropEntering = false;
         updateRecentTasksSplitPair();
         if (!mLogger.hasStartedSession()) {
             mLogger.logEnter(mSplitLayout.getDividerPositionAsFraction(),
@@ -1777,18 +1781,10 @@ public class StageCoordinator implements SplitLayout.SplitLayoutHandler,
         // Handle entering split screen while there is a split pair running in the background.
         if (stageListener == mSideStageListener && !isSplitScreenVisible() && isSplitActive()
                 && mSplitRequest == null) {
-            if (mIsDropEntering) {
-                mSplitLayout.resetDividerPosition();
-            } else {
-                mSplitLayout.setDividerAtBorder(mSideStagePosition == SPLIT_POSITION_TOP_OR_LEFT);
-            }
             final WindowContainerTransaction wct = new WindowContainerTransaction();
-            mMainStage.reparentTopTask(wct);
+            prepareEnterSplitScreen(wct);
             mMainStage.evictAllChildren(wct);
             mSideStage.evictOtherChildren(wct, taskId);
-            updateWindowBounds(mSplitLayout, wct);
-            wct.reorder(mRootTaskInfo.token, true);
-            setRootForceTranslucent(false, wct);
 
             mSyncQueue.queue(wct);
             mSyncQueue.runInSync(t -> {
@@ -1983,20 +1979,8 @@ public class StageCoordinator implements SplitLayout.SplitLayoutHandler,
                 exitSplitScreen(null /* childrenToTop */, EXIT_REASON_APP_FINISHED);
             }
         } else if (isSideStage && hasChildren && !mMainStage.isActive()) {
-            mSplitLayout.init();
-
             final WindowContainerTransaction wct = new WindowContainerTransaction();
-            if (mIsDropEntering) {
+            prepareEnterSplitScreen(wct);
-                prepareEnterSplitScreen(wct);
-            } else {
-                // TODO (b/238697912) : Add the validation to prevent entering non-recovered status
-                onSplitScreenEnter();
-                mSplitLayout.setDividerAtBorder(mSideStagePosition == SPLIT_POSITION_TOP_OR_LEFT);
-                mMainStage.activate(wct, true /* includingTopTask */);
-                updateWindowBounds(mSplitLayout, wct);
-                wct.reorder(mRootTaskInfo.token, true);
-                setRootForceTranslucent(false, wct);
-            }
 
             mSyncQueue.queue(wct);
             mSyncQueue.runInSync(t -> {
@@ -2353,7 +2337,7 @@ public class StageCoordinator implements SplitLayout.SplitLayoutHandler,
                 prepareEnterSplitScreen(out);
                 mSplitTransitions.setEnterTransition(transition, request.getRemoteTransition(),
                         null /* consumedCallback */, null /* finishedCallback */,
-                        0 /* extraTransitType */);
+                        0 /* extraTransitType */, !mIsDropEntering);
             }
         }
         return out;
@@ -2596,7 +2580,7 @@ public class StageCoordinator implements SplitLayout.SplitLayoutHandler,
     }
 
     private boolean startPendingEnterAnimation(
-            @NonNull SplitScreenTransitions.TransitSession enterTransition,
+            @NonNull SplitScreenTransitions.EnterSession enterTransition,
             @NonNull TransitionInfo info, @NonNull SurfaceControl.Transaction t,
             @NonNull SurfaceControl.Transaction finishT) {
         // First, verify that we actually have opened apps in both splits.
@@ -2654,7 +2638,6 @@ public class StageCoordinator implements SplitLayout.SplitLayoutHandler,
                     + " to have been called with " + sideChild.getTaskInfo().taskId
                     + " before startAnimation().");
         }
-
         final TransitionInfo.Change finalMainChild = mainChild;
         final TransitionInfo.Change finalSideChild = sideChild;
         enterTransition.setFinishedCallback((callbackWct, callbackT) -> {
@@ -2664,6 +2647,10 @@ public class StageCoordinator implements SplitLayout.SplitLayoutHandler,
             if (finalSideChild != null) {
                 mSideStage.evictOtherChildren(callbackWct, finalSideChild.getTaskInfo().taskId);
             }
+            if (enterTransition.mResizeAnim) {
+                mShowDecorImmediately = true;
+                mSplitLayout.flingDividerToCenter();
+            }
         });
 
         finishEnterSplitScreen(finishT);

libs/WindowManager/Shell/tests/unittest/src/com/android/wm/shell/splitscreen/SplitTransitionTests.java

@@ -182,7 +182,7 @@ public class SplitTransitionTests extends ShellTestCase {
         IBinder transition = mSplitScreenTransitions.startEnterTransition(
                 TRANSIT_OPEN, new WindowContainerTransaction(),
                 new RemoteTransition(testRemote, "Test"), mStageCoordinator, null, null,
-                TRANSIT_SPLIT_SCREEN_PAIR_OPEN);
+                TRANSIT_SPLIT_SCREEN_PAIR_OPEN, false);
         mMainStage.onTaskAppeared(mMainChild, createMockSurface());
         mSideStage.onTaskAppeared(mSideChild, createMockSurface());
         boolean accepted = mStageCoordinator.startAnimation(transition, info,
@@ -408,7 +408,7 @@ public class SplitTransitionTests extends ShellTestCase {
         IBinder enterTransit = mSplitScreenTransitions.startEnterTransition(
                 TRANSIT_OPEN, new WindowContainerTransaction(),
                 new RemoteTransition(new TestRemoteTransition(), "Test"),
-                mStageCoordinator, null, null, TRANSIT_SPLIT_SCREEN_PAIR_OPEN);
+                mStageCoordinator, null, null, TRANSIT_SPLIT_SCREEN_PAIR_OPEN, false);
         mMainStage.onTaskAppeared(mMainChild, createMockSurface());
         mSideStage.onTaskAppeared(mSideChild, createMockSurface());
         mStageCoordinator.startAnimation(enterTransit, enterInfo,

libs/WindowManager/Shell/tests/unittest/src/com/android/wm/shell/splitscreen/StageCoordinatorTests.java

@@ -158,7 +158,6 @@ public class StageCoordinatorTests extends ShellTestCase {
         verify(mStageCoordinator).prepareEnterSplitScreen(eq(wct), eq(task),
                 eq(SPLIT_POSITION_BOTTOM_OR_RIGHT));
         verify(mMainStage).reparentTopTask(eq(wct));
-        verify(mSplitLayout).resetDividerPosition();
         assertEquals(SPLIT_POSITION_BOTTOM_OR_RIGHT, mStageCoordinator.getSideStagePosition());
         assertEquals(SPLIT_POSITION_TOP_OR_LEFT, mStageCoordinator.getMainStagePosition());
     }