Centralize assignment of pip enter animation type

In PipTransition, the places to check enter animation type
may have different orders with different scenarios.

Assume swiping a fullscreen landscape app which can enter PiP
to portrait home:

Api request on foreground:
  augmentRequest -> startEnterAnimation -> handleRotateDisplay
Api request on going to background:
  startEnterAnimation -> handleRotateDisplay

Swipe to home:
 Auto-pip:
  augmentRequest -> handleRotateDisplay -> startEnterAnimation
 No auto-pip:
  handleRotateDisplay -> startEnterAnimation

To reduce the complexity of animation type management, assign
the type at entry of entering pip: PipTaskOrganizer#onTaskAppeared
Then PipTransition only needs to read it.

Note that for swiping auto-pip, the type is always ignored
because the animation is done by recents animation.

Bug: 276438425
Test: Swipe a landscape app into pip in portrait without auto-pip.
      The PiP should fade in after the swipe animation.

Change-Id: I98e459fb9913d713cd3b8d44dbb691af61862c56

libs/WindowManager/Shell/src/com/android/wm/shell/pip/PipTaskOrganizer.java

@@ -712,15 +712,16 @@ public class PipTaskOrganizer implements ShellTaskOrganizer.TaskListener,
             return;
         }
 
+        final int animationType = shouldAlwaysFadeIn()
+                ? ANIM_TYPE_ALPHA
+                : mPipAnimationController.takeOneShotEnterAnimationType();
         if (Transitions.ENABLE_SHELL_TRANSITIONS) {
+            mPipTransitionController.setEnterAnimationType(animationType);
             // For Shell transition, we will animate the window in PipTransition#startAnimation
             // instead of #onTaskAppeared.
             return;
         }
 
-        final int animationType = shouldAlwaysFadeIn()
-                ? ANIM_TYPE_ALPHA
-                : mPipAnimationController.takeOneShotEnterAnimationType();
         if (mWaitForFixedRotation) {
             onTaskAppearedWithFixedRotation(animationType);
             return;

libs/WindowManager/Shell/src/com/android/wm/shell/pip/PipTransition.java

@@ -274,9 +274,6 @@ public class PipTransition extends PipTransitionController {
         if (!requestHasPipEnter(request)) {
             throw new IllegalStateException("Called PiP augmentRequest when request has no PiP");
         }
-        mEnterAnimationType = mPipOrganizer.shouldAlwaysFadeIn()
-                ? ANIM_TYPE_ALPHA
-                : mPipAnimationController.takeOneShotEnterAnimationType();
         if (mEnterAnimationType == ANIM_TYPE_ALPHA) {
             mRequestedEnterTransition = transition;
             mRequestedEnterTask = request.getTriggerTask().token;
@@ -665,6 +662,11 @@ public class PipTransition extends PipTransitionController {
         return false;
     }
 
+    @Override
+    public void setEnterAnimationType(@PipAnimationController.AnimationType int type) {
+        mEnterAnimationType = type;
+    }
+
     private void startEnterAnimation(@NonNull TransitionInfo info,
             @NonNull SurfaceControl.Transaction startTransaction,
             @NonNull SurfaceControl.Transaction finishTransaction,
@@ -786,8 +788,6 @@ public class PipTransition extends PipTransitionController {
 
         final int enterAnimationType = mEnterAnimationType;
         if (enterAnimationType == ANIM_TYPE_ALPHA) {
-            // Restore to default type.
-            mEnterAnimationType = ANIM_TYPE_BOUNDS;
             startTransaction.setAlpha(leash, 0f);
         }
         startTransaction.apply();

libs/WindowManager/Shell/src/com/android/wm/shell/pip/PipTransitionController.java

@@ -225,6 +225,10 @@ public abstract class PipTransitionController implements Transitions.TransitionH
         throw new IllegalStateException("Request isn't entering PiP");
     }
 
+    /** Sets the type of animation when a PiP task appears. */
+    public void setEnterAnimationType(@PipAnimationController.AnimationType int type) {
+    }
+
     /** Play a transition animation for entering PiP on a specific PiP change. */
     public void startEnterAnimation(@NonNull final TransitionInfo.Change pipChange,
             @NonNull final SurfaceControl.Transaction startTransaction,