Move detection of cutouts in Android engine to onApplyWindowInsets (#55992)

Stop including the translation of window insets cutouts to Flutter
cutout DisplayFeatures in the window info listener method, which would
not necessarily receive changes in the correct order/state when they
update, e.g. when the screen orientation changes.

Fixes flutter/flutter#155658

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Author: yaakovschectman

shell/platform/android/io/flutter/embedding/android/FlutterView.java

@@ -196,13 +196,7 @@ public void onFlutterUiNoLongerDisplayed() {
         }
       };
 
-  private final Consumer<WindowLayoutInfo> windowInfoListener =
-      new Consumer<WindowLayoutInfo>() {
-        @Override
-        public void accept(WindowLayoutInfo layoutInfo) {
-          setWindowInfoListenerDisplayFeatures(layoutInfo);
-        }
-      };
+  private Consumer<WindowLayoutInfo> windowInfoListener;
 
   /**
    * Constructs a {@code FlutterView} programmatically, without any XML attributes.
@@ -514,6 +508,10 @@ protected void onAttachedToWindow() {
     this.windowInfoRepo = createWindowInfoRepo();
     Activity activity = ViewUtils.getActivity(getContext());
     if (windowInfoRepo != null && activity != null) {
+      // Creating windowInfoListener on-demand instead of at initialization is necessary in order to
+      // prevent it from capturing the wrong instance of `this` when spying for testing.
+      // See https://github.com/mockito/mockito/issues/3479
+      windowInfoListener = this::setWindowInfoListenerDisplayFeatures;
       windowInfoRepo.addWindowLayoutInfoListener(
           activity, ContextCompat.getMainExecutor(getContext()), windowInfoListener);
     }
@@ -526,9 +524,10 @@ protected void onAttachedToWindow() {
    */
   @Override
   protected void onDetachedFromWindow() {
-    if (windowInfoRepo != null) {
+    if (windowInfoRepo != null && windowInfoListener != null) {
       windowInfoRepo.removeWindowLayoutInfoListener(windowInfoListener);
     }
+    windowInfoListener = null;
     this.windowInfoRepo = null;
     super.onDetachedFromWindow();
   }
@@ -539,12 +538,12 @@ protected void onDetachedFromWindow() {
    */
   @TargetApi(API_LEVELS.API_28)
   protected void setWindowInfoListenerDisplayFeatures(WindowLayoutInfo layoutInfo) {
-    List<DisplayFeature> displayFeatures = layoutInfo.getDisplayFeatures();
-    List<FlutterRenderer.DisplayFeature> result = new ArrayList<>();
+    List<DisplayFeature> newDisplayFeatures = layoutInfo.getDisplayFeatures();
+    List<FlutterRenderer.DisplayFeature> flutterDisplayFeatures = new ArrayList<>();
 
     // Data from WindowInfoTracker display features. Fold and hinge areas are
     // populated here.
-    for (DisplayFeature displayFeature : displayFeatures) {
+    for (DisplayFeature displayFeature : newDisplayFeatures) {
       Log.v(
           TAG,
           "WindowInfoTracker Display Feature reported with bounds = "
@@ -567,31 +566,17 @@ protected void setWindowInfoListenerDisplayFeatures(WindowLayoutInfo layoutInfo)
         } else {
           state = DisplayFeatureState.UNKNOWN;
         }
-        result.add(new FlutterRenderer.DisplayFeature(displayFeature.getBounds(), type, state));
+        flutterDisplayFeatures.add(
+            new FlutterRenderer.DisplayFeature(displayFeature.getBounds(), type, state));
       } else {
-        result.add(
+        flutterDisplayFeatures.add(
             new FlutterRenderer.DisplayFeature(
                 displayFeature.getBounds(),
                 DisplayFeatureType.UNKNOWN,
                 DisplayFeatureState.UNKNOWN));
       }
     }
-
-    // Data from the DisplayCutout bounds. Cutouts for cameras and other sensors are
-    // populated here. DisplayCutout was introduced in API 28.
-    if (Build.VERSION.SDK_INT >= API_LEVELS.API_28) {
-      WindowInsets insets = getRootWindowInsets();
-      if (insets != null) {
-        DisplayCutout cutout = insets.getDisplayCutout();
-        if (cutout != null) {
-          for (Rect bounds : cutout.getBoundingRects()) {
-            Log.v(TAG, "DisplayCutout area reported with bounds = " + bounds.toString());
-            result.add(new FlutterRenderer.DisplayFeature(bounds, DisplayFeatureType.CUTOUT));
-          }
-        }
-      }
-    }
-    viewportMetrics.displayFeatures = result;
+    viewportMetrics.setDisplayFeatures(flutterDisplayFeatures);
     sendViewportMetricsToFlutter();
   }
 
@@ -784,6 +769,22 @@ navigationBarVisible && guessBottomKeyboardInset(insets) == 0
       viewportMetrics.viewInsetLeft = 0;
     }
 
+    // Data from the DisplayCutout bounds. Cutouts for cameras and other sensors are
+    // populated here. DisplayCutout was introduced in API 28.
+    List<FlutterRenderer.DisplayFeature> displayCutouts = new ArrayList<>();
+    if (Build.VERSION.SDK_INT >= API_LEVELS.API_28) {
+      DisplayCutout cutout = insets.getDisplayCutout();
+      if (cutout != null) {
+        for (Rect bounds : cutout.getBoundingRects()) {
+          Log.v(TAG, "DisplayCutout area reported with bounds = " + bounds.toString());
+          displayCutouts.add(
+              new FlutterRenderer.DisplayFeature(
+                  bounds, DisplayFeatureType.CUTOUT, DisplayFeatureState.UNKNOWN));
+        }
+      }
+    }
+    viewportMetrics.setDisplayCutouts(displayCutouts);
+
     // The caption bar inset is a new addition, and the APIs called to query it utilize a list of
     // bounding Rects instead of an Insets object, which is a newer API method, as compared to the
     // existing Insets-based method calls above.

shell/platform/android/io/flutter/embedding/engine/renderer/FlutterRenderer.java

@@ -1157,6 +1157,13 @@ public void stopRenderingToSurface() {
     }
   }
 
+  private void translateFeatureBounds(int[] displayFeatureBounds, int offset, Rect bounds) {
+    displayFeatureBounds[offset] = bounds.left;
+    displayFeatureBounds[offset + 1] = bounds.top;
+    displayFeatureBounds[offset + 2] = bounds.right;
+    displayFeatureBounds[offset + 3] = bounds.bottom;
+  }
+
   /**
    * Notifies Flutter that the viewport metrics, e.g. window height and width, have changed.
    *
@@ -1207,20 +1214,31 @@ public void setViewportMetrics(@NonNull ViewportMetrics viewportMetrics) {
             + viewportMetrics.systemGestureInsetRight
             + "\n"
             + "Display Features: "
-            + viewportMetrics.displayFeatures.size());
-
-    int[] displayFeaturesBounds = new int[viewportMetrics.displayFeatures.size() * 4];
-    int[] displayFeaturesType = new int[viewportMetrics.displayFeatures.size()];
-    int[] displayFeaturesState = new int[viewportMetrics.displayFeatures.size()];
+            + viewportMetrics.displayFeatures.size()
+            + "\n"
+            + "Display Cutouts: "
+            + viewportMetrics.displayCutouts.size());
+
+    int totalFeaturesAndCutouts =
+        viewportMetrics.displayFeatures.size() + viewportMetrics.displayCutouts.size();
+    int[] displayFeaturesBounds = new int[totalFeaturesAndCutouts * 4];
+    int[] displayFeaturesType = new int[totalFeaturesAndCutouts];
+    int[] displayFeaturesState = new int[totalFeaturesAndCutouts];
     for (int i = 0; i < viewportMetrics.displayFeatures.size(); i++) {
       DisplayFeature displayFeature = viewportMetrics.displayFeatures.get(i);
-      displayFeaturesBounds[4 * i] = displayFeature.bounds.left;
-      displayFeaturesBounds[4 * i + 1] = displayFeature.bounds.top;
-      displayFeaturesBounds[4 * i + 2] = displayFeature.bounds.right;
-      displayFeaturesBounds[4 * i + 3] = displayFeature.bounds.bottom;
+      translateFeatureBounds(displayFeaturesBounds, 4 * i, displayFeature.bounds);
       displayFeaturesType[i] = displayFeature.type.encodedValue;
       displayFeaturesState[i] = displayFeature.state.encodedValue;
     }
+    int cutoutOffset = viewportMetrics.displayFeatures.size() * 4;
+    for (int i = 0; i < viewportMetrics.displayCutouts.size(); i++) {
+      DisplayFeature displayCutout = viewportMetrics.displayCutouts.get(i);
+      translateFeatureBounds(displayFeaturesBounds, cutoutOffset + 4 * i, displayCutout.bounds);
+      displayFeaturesType[viewportMetrics.displayFeatures.size() + i] =
+          displayCutout.type.encodedValue;
+      displayFeaturesState[viewportMetrics.displayFeatures.size() + i] =
+          displayCutout.state.encodedValue;
+    }
 
     flutterJNI.setViewportMetrics(
         viewportMetrics.devicePixelRatio,
@@ -1335,7 +1353,29 @@ boolean validate() {
       return width > 0 && height > 0 && devicePixelRatio > 0;
     }
 
-    public List<DisplayFeature> displayFeatures = new ArrayList<>();
+    // Features
+    private final List<DisplayFeature> displayFeatures = new ArrayList<>();
+
+    // Specifically display cutouts.
+    private final List<DisplayFeature> displayCutouts = new ArrayList<>();
+
+    public List<DisplayFeature> getDisplayFeatures() {
+      return displayFeatures;
+    }
+
+    public List<DisplayFeature> getDisplayCutouts() {
+      return displayCutouts;
+    }
+
+    public void setDisplayFeatures(List<DisplayFeature> newFeatures) {
+      displayFeatures.clear();
+      displayFeatures.addAll(newFeatures);
+    }
+
+    public void setDisplayCutouts(List<DisplayFeature> newCutouts) {
+      displayCutouts.clear();
+      displayCutouts.addAll(newCutouts);
+    }
   }
 
   /**
@@ -1358,12 +1398,6 @@ public DisplayFeature(Rect bounds, DisplayFeatureType type, DisplayFeatureState
       this.type = type;
       this.state = state;
     }
-
-    public DisplayFeature(Rect bounds, DisplayFeatureType type) {
-      this.bounds = bounds;
-      this.type = type;
-      this.state = DisplayFeatureState.UNKNOWN;
-    }
   }
 
   /**