Add workaround for new back flow with legacy recents animation

- Override the callback to inject back as we do today while in Overview.
  We can't rely on the client side compat callback because the Launcher
  window is not focused in this current state.

Bug: 223750399
Test: Open overview, swipe back
Change-Id: I1978ce3a91cba3e57c0f8bab366691b48a9d5921

data/etc/services.core.protolog.json

@@ -1657,6 +1657,12 @@
       "group": "WM_DEBUG_ADD_REMOVE",
       "at": "com\/android\/server\/wm\/Task.java"
     },
+    "-451552570": {
+      "message": "Current focused window being animated by recents. Overriding back callback to recents controller callback.",
+      "level": "DEBUG",
+      "group": "WM_DEBUG_BACK_PREVIEW",
+      "at": "com\/android\/server\/wm\/BackNavigationController.java"
+    },
     "-449118559": {
       "message": "Trying to update display configuration for invalid process, pid=%d",
       "level": "WARN",
@@ -2917,12 +2923,6 @@
       "group": "WM_DEBUG_LOCKTASK",
       "at": "com\/android\/server\/wm\/ActivityTaskManagerService.java"
     },
-    "716528224": {
-      "message": "Focused window found using wmService.getFocusedWindowLocked()",
-      "level": "DEBUG",
-      "group": "WM_DEBUG_BACK_PREVIEW",
-      "at": "com\/android\/server\/wm\/BackNavigationController.java"
-    },
     "726205185": {
       "message": "Moving to DESTROYED: %s (destroy skipped)",
       "level": "VERBOSE",

services/core/java/com/android/server/wm/BackNavigationController.java

@@ -145,6 +145,27 @@ class BackNavigationController {
                         "Focused window found using getFocusedWindowToken");
             }
 
+            OnBackInvokedCallbackInfo overrideCallbackInfo = null;
+            if (window != null) {
+                // This is needed to bridge the old and new back behavior with recents.  While in
+                // Overview with live tile enabled, the previous app is technically focused but we
+                // add an input consumer to capture all input that would otherwise go to the apps
+                // being controlled by the animation. This means that the window resolved is not
+                // the right window to consume back while in overview, so we need to route it to
+                // launcher and use the legacy behavior of injecting KEYCODE_BACK since the existing
+                // compat callback in VRI only works when the window is focused.
+                final RecentsAnimationController recentsAnimationController =
+                        wmService.getRecentsAnimationController();
+                if (recentsAnimationController != null
+                        && recentsAnimationController.shouldApplyInputConsumer(
+                        window.getActivityRecord())) {
+                    window = recentsAnimationController.getTargetAppMainWindow();
+                    overrideCallbackInfo = recentsAnimationController.getBackInvokedInfo();
+                    ProtoLog.d(WM_DEBUG_BACK_PREVIEW, "Current focused window being animated by "
+                            + "recents. Overriding back callback to recents controller callback.");
+                }
+            }
+
             if (window == null) {
                 // We don't have any focused window, fallback ont the top currentTask of the focused
                 // display.
@@ -159,7 +180,9 @@ class BackNavigationController {
             if (window != null) {
                 currentActivity = window.mActivityRecord;
                 currentTask = window.getTask();
-                callbackInfo = window.getOnBackInvokedCallbackInfo();
+                callbackInfo = overrideCallbackInfo != null
+                        ? overrideCallbackInfo
+                        : window.getOnBackInvokedCallbackInfo();
                 if (callbackInfo == null) {
                     Slog.e(TAG, "No callback registered, returning null.");
                     return null;

services/core/java/com/android/server/wm/RecentsAnimationController.java

@@ -19,10 +19,12 @@ package com.android.server.wm;
 import static android.app.ActivityTaskManager.INVALID_TASK_ID;
 import static android.app.WindowConfiguration.ACTIVITY_TYPE_HOME;
 import static android.app.WindowConfiguration.WINDOWING_MODE_UNDEFINED;
+import static android.hardware.input.InputManager.INJECT_INPUT_EVENT_MODE_ASYNC;
 import static android.view.RemoteAnimationTarget.MODE_CLOSING;
 import static android.view.RemoteAnimationTarget.MODE_OPENING;
 import static android.view.WindowManager.INPUT_CONSUMER_RECENTS_ANIMATION;
 import static android.view.WindowManager.LayoutParams.TYPE_BASE_APPLICATION;
+import static android.window.OnBackInvokedDispatcher.PRIORITY_DEFAULT;
 
 import static com.android.internal.protolog.ProtoLogGroup.WM_DEBUG_RECENTS_ANIMATIONS;
 import static com.android.server.policy.WindowManagerPolicy.FINISH_LAYOUT_REDO_WALLPAPER;
@@ -39,6 +41,7 @@ import android.graphics.GraphicBuffer;
 import android.graphics.Point;
 import android.graphics.Rect;
 import android.hardware.HardwareBuffer;
+import android.hardware.input.InputManager;
 import android.os.Binder;
 import android.os.IBinder.DeathRecipient;
 import android.os.RemoteException;
@@ -51,12 +54,18 @@ import android.util.SparseBooleanArray;
 import android.util.proto.ProtoOutputStream;
 import android.view.IRecentsAnimationController;
 import android.view.IRecentsAnimationRunner;
+import android.view.InputDevice;
 import android.view.InputWindowHandle;
+import android.view.KeyCharacterMap;
+import android.view.KeyEvent;
 import android.view.RemoteAnimationTarget;
 import android.view.SurfaceControl;
 import android.view.SurfaceControl.Transaction;
 import android.view.SurfaceSession;
 import android.view.WindowInsets.Type;
+import android.window.BackEvent;
+import android.window.IOnBackInvokedCallback;
+import android.window.OnBackInvokedCallbackInfo;
 import android.window.PictureInPictureSurfaceTransaction;
 import android.window.TaskSnapshot;
 
@@ -194,6 +203,46 @@ public class RecentsAnimationController implements DeathRecipient {
         }
     };
 
+    /**
+     * Back invoked callback for legacy recents transition with the new back dispatch system.
+     */
+    final IOnBackInvokedCallback mBackCallback = new IOnBackInvokedCallback.Stub() {
+        @Override
+        public void onBackStarted() {
+            // Do nothing
+        }
+
+        @Override
+        public void onBackProgressed(BackEvent backEvent) {
+            // Do nothing
+        }
+
+        @Override
+        public void onBackCancelled() {
+            // Do nothing
+        }
+
+        @Override
+        public void onBackInvoked() {
+            sendBackEvent(KeyEvent.ACTION_DOWN);
+            sendBackEvent(KeyEvent.ACTION_UP);
+        }
+
+        private void sendBackEvent(int action) {
+            if (mTargetActivityRecord == null) {
+                return;
+            }
+            long when = SystemClock.uptimeMillis();
+            final KeyEvent ev = new KeyEvent(when, when, action,
+                    KeyEvent.KEYCODE_BACK, 0 /* repeat */, 0 /* metaState */,
+                    KeyCharacterMap.VIRTUAL_KEYBOARD, 0 /* scancode */,
+                    KeyEvent.FLAG_FROM_SYSTEM | KeyEvent.FLAG_VIRTUAL_HARD_KEY,
+                    InputDevice.SOURCE_KEYBOARD);
+            ev.setDisplayId(mTargetActivityRecord.getDisplayId());
+            InputManager.getInstance().injectInputEvent(ev, INJECT_INPUT_EVENT_MODE_ASYNC);
+        }
+    };
+
     public interface RecentsAnimationCallbacks {
         /** Callback when recents animation is finished. */
         void onAnimationFinished(@ReorderMode int reorderMode, boolean sendUserLeaveHint);
@@ -1104,6 +1153,10 @@ public class RecentsAnimationController implements DeathRecipient {
         return mTargetActivityRecord.findMainWindow();
     }
 
+    OnBackInvokedCallbackInfo getBackInvokedInfo() {
+        return new OnBackInvokedCallbackInfo(mBackCallback, PRIORITY_DEFAULT);
+    }
+
     DisplayArea getTargetAppDisplayArea() {
         if (mTargetActivityRecord == null) {
             return null;