[aw] Reuse WebContents PowerSaveBlocker in fullscreen.

content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java

Index: content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java
diff --git a/content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java b/content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java
index ba0c70ebeaa44f086df6ca89bf046cf7f4b47a4d..e9cdf106c14156f9153785c012c30a53ddf08f0e 100644
--- a/content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java
+++ b/content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java
@@ -87,8 +87,10 @@ import java.lang.reflect.Field;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.HashSet;
+import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Map.Entry;
 
 /**
  * Provides a Java-side 'wrapper' around a WebContent (native) instance.
@@ -143,6 +145,136 @@ public class ContentViewCore
     private final HashSet<Object> mRetainedJavaScriptObjects = new HashSet<Object>();
 
     /**
+     * A {@link ViewAndroidDelegate} that delegates to the current container view.
+     *
+     * <p>This delegate handles the replacement of container views transparently so
+     * that clients can safely hold to instances of this class.
+     */
+    private class ContentViewAndroidDelegate implements ViewAndroidDelegate {
+        /**
+         * Represents the position of an anchor view.
+         */
+        @VisibleForTesting
+        private class Position {
+            private final float mX;
+            private final float mY;
+            private final float mWidth;
+            private final float mHeight;
+
+            public Position(float x, float y, float width, float height) {
+                mX = x;
+                mY = y;
+                mWidth = width;
+                mHeight = height;
+            }
+        }
+
+        /**
+         * The current container view. This view can be updated with
+         * {@link #updateCurrentContainerView()}.
+         */
+        private ViewGroup mCurrentContainerView;
+
+        /**
+         * List of anchor views stored in the order in which they were acquired mapped
+         * to their position.
+         */
+        private Map<View, Position> mAnchorViews = new LinkedHashMap<View, Position>();
+
+        @Override
+        public View acquireAnchorView() {
+            View anchorView = new View(mContext);
+            mAnchorViews.put(anchorView, null);
+            mCurrentContainerView.addView(anchorView);
+            return anchorView;
+        }
+
+        @Override
+        @SuppressWarnings("deprecation")  // AbsoluteLayout
+        public void setAnchorViewPosition(
+                View view, float x, float y, float width, float height) {
+            mAnchorViews.put(view, new Position(x, y, width, height));
+            doSetAnchorViewPosition(view, x, y, width, height);
+        }
+
+        private void doSetAnchorViewPosition(
+                View view, float x, float y, float width, float height) {
+            if (view.getParent() == null) {
+                // Ignore. setAnchorViewPosition has been called after the anchor view has
+                // already been released.
+                return;
+            }
+            assert view.getParent() == mCurrentContainerView;
+
+            float scale = (float) DeviceDisplayInfo.create(mContext).getDIPScale();
+
+            // The anchor view should not go outside the bounds of the ContainerView.
+            int leftMargin = Math.round(x * scale);
+            int topMargin = Math.round(mRenderCoordinates.getContentOffsetYPix() + y * scale);
+            int scaledWidth = Math.round(width * scale);
+            // ContentViewCore currently only supports these two container view types.
+            if (mCurrentContainerView instanceof FrameLayout) {
+                int startMargin;
+                if (ApiCompatibilityUtils.isLayoutRtl(mCurrentContainerView)) {
+                    startMargin = mCurrentContainerView.getMeasuredWidth()
+                            - Math.round((width + x) * scale);
+                } else {
+                    startMargin = leftMargin;
+                }
+                if (scaledWidth + startMargin > mCurrentContainerView.getWidth()) {
+                    scaledWidth = mCurrentContainerView.getWidth() - startMargin;
+                }
+                FrameLayout.LayoutParams lp = new FrameLayout.LayoutParams(
+                        scaledWidth, Math.round(height * scale));
+                ApiCompatibilityUtils.setMarginStart(lp, startMargin);
+                lp.topMargin = topMargin;
+                view.setLayoutParams(lp);
+            } else if (mCurrentContainerView instanceof android.widget.AbsoluteLayout) {
+                // This fixes the offset due to a difference in
+                // scrolling model of WebView vs. Chrome.
+                // TODO(sgurun) fix this to use mContainerViewAtCreation.getScroll[X/Y]()
+                // as it naturally accounts for scroll differences between
+                // these models.
+                leftMargin += mRenderCoordinates.getScrollXPixInt();
+                topMargin += mRenderCoordinates.getScrollYPixInt();
+
+                android.widget.AbsoluteLayout.LayoutParams lp =
+                        new android.widget.AbsoluteLayout.LayoutParams(
+                            scaledWidth, (int) (height * scale), leftMargin, topMargin);
+                view.setLayoutParams(lp);
+            } else {
+                Log.e(TAG, "Unknown layout " + mCurrentContainerView.getClass().getName());
+            }
+        }
+
+        @Override
+        public void releaseAnchorView(View anchorView) {
+            mAnchorViews.remove(anchorView);
+            mCurrentContainerView.removeView(anchorView);
+        }
+
+        /**
+         * Updates (or sets for the first time) the current container view to which
+         * this class delegates. Existing anchor views are transferred from the old to
+         * the new container view.
+         */
+        void updateCurrentContainerView() {
+            ViewGroup oldContainerView = mCurrentContainerView;
+            mCurrentContainerView = mContainerView;
+            for (Entry<View, Position> entry : mAnchorViews.entrySet()) {
+                View anchorView = entry.getKey();
+                Position position = entry.getValue();
+                oldContainerView.removeView(anchorView);
+                mCurrentContainerView.addView(anchorView);
+                if (position != null) {
+                    doSetAnchorViewPosition(anchorView,
+                            position.mX, position.mY, position.mWidth, position.mHeight);
+                }
+            }
+        }
+    }
+
+    /**
      * Interface that consumers of {@link ContentViewCore} must implement to allow the proper
      * dispatching of view methods through the containing view.
      *
@@ -361,6 +493,9 @@ public class ContentViewCore
     // screen orientation.
     private boolean mFullscreenRequiredForOrientationLock = true;
 
+    // A ViewAndroidDelegate that delegates to the current container view.
+    private ContentViewAndroidDelegate mViewAndroidDelegate;
+
     /**
      * Constructs a new ContentViewCore. Embedders must call initialize() after constructing
      * a ContentViewCore and before using it.
@@ -429,9 +564,11 @@ public class ContentViewCore
     }
 
     /**
-     * Returns a delegate that can be used to add and remove views from the ContainerView.
+     * Returns a delegate that can be used to add and remove views from the current
+     * container view. Clients can safely hold to instances of this class as it handles the
+     * replacement of container views transparently.
      *
-     * NOTE: Use with care, as not all ContentViewCore users setup their ContainerView in the same
+     * NOTE: Use with care, as not all ContentViewCore users setup their container view in the same
      * way. In particular, the Android WebView has limitations on what implementation details can
      * be provided via a child view, as they are visible in the API and could introduce
      * compatibility breaks with existing applications. If in doubt, contact the
@@ -439,77 +576,8 @@ public class ContentViewCore
      *
      * @return A ViewAndroidDelegate that can be used to add and remove views.
      */
-    @VisibleForTesting
     public ViewAndroidDelegate getViewAndroidDelegate() {
-        return new ViewAndroidDelegate() {
-            // mContainerView can change, but this ViewAndroidDelegate can only be used to
-            // add and remove views from the mContainerViewAtCreation.
-            private final ViewGroup mContainerViewAtCreation = mContainerView;
-
-            @Override
-            public View acquireAnchorView() {
-                View anchorView = new View(mContext);
-                mContainerViewAtCreation.addView(anchorView);
-                return anchorView;
-            }
-
-            @Override
-            @SuppressWarnings("deprecation")  // AbsoluteLayout
-            public void setAnchorViewPosition(
-                    View view, float x, float y, float width, float height) {
-                if (view.getParent() == null) {
-                    // Ignore. setAnchorViewPosition has been called after the anchor view has
-                    // already been released.
-                    return;
-                }
-                assert view.getParent() == mContainerViewAtCreation;
-
-                float scale = (float) DeviceDisplayInfo.create(mContext).getDIPScale();
-
-                // The anchor view should not go outside the bounds of the ContainerView.
-                int leftMargin = Math.round(x * scale);
-                int topMargin = Math.round(mRenderCoordinates.getContentOffsetYPix() + y * scale);
-                int scaledWidth = Math.round(width * scale);
-                // ContentViewCore currently only supports these two container view types.
-                if (mContainerViewAtCreation instanceof FrameLayout) {
-                    int startMargin;
-                    if (ApiCompatibilityUtils.isLayoutRtl(mContainerViewAtCreation)) {
-                        startMargin = mContainerViewAtCreation.getMeasuredWidth()
-                                - Math.round((width + x) * scale);
-                    } else {
-                        startMargin = leftMargin;
-                    }
-                    if (scaledWidth + startMargin > mContainerViewAtCreation.getWidth()) {
-                        scaledWidth = mContainerViewAtCreation.getWidth() - startMargin;
-                    }
-                    FrameLayout.LayoutParams lp = new FrameLayout.LayoutParams(
-                            scaledWidth, Math.round(height * scale));
-                    ApiCompatibilityUtils.setMarginStart(lp, startMargin);
-                    lp.topMargin = topMargin;
-                    view.setLayoutParams(lp);
-                } else if (mContainerViewAtCreation instanceof android.widget.AbsoluteLayout) {
-                    // This fixes the offset due to a difference in
-                    // scrolling model of WebView vs. Chrome.
-                    // TODO(sgurun) fix this to use mContainerViewAtCreation.getScroll[X/Y]()
-                    // as it naturally accounts for scroll differences between
-                    // these models.
-                    leftMargin += mRenderCoordinates.getScrollXPixInt();
-                    topMargin += mRenderCoordinates.getScrollYPixInt();
-
-                    android.widget.AbsoluteLayout.LayoutParams lp =
-                            new android.widget.AbsoluteLayout.LayoutParams(
-                                scaledWidth, (int) (height * scale), leftMargin, topMargin);
-                    view.setLayoutParams(lp);
-                } else {
-                    Log.e(TAG, "Unknown layout " + mContainerViewAtCreation.getClass().getName());
-                }
-            }
-
-            @Override
-            public void releaseAnchorView(View anchorView) {
-                mContainerViewAtCreation.removeView(anchorView);
-            }
-        };
+        return mViewAndroidDelegate;
     }
 
     @VisibleForTesting
@@ -537,6 +605,11 @@ public class ContentViewCore
         return mInputConnection;
     }
 
+    @VisibleForTesting
+    ViewAndroid getViewAndroid() {
+        return mViewAndroid;
+    }
+
     private ImeAdapter createImeAdapter(Context context) {
         return new ImeAdapter(mInputMethodManagerWrapper,
                 new ImeAdapter.ImeAdapterDelegate() {
@@ -605,11 +678,12 @@ public class ContentViewCore
     // deleting it after destroying the ContentViewCore.
     public void initialize(ViewGroup containerView, InternalAccessDelegate internalDispatcher,
             long nativeWebContents, WindowAndroid windowAndroid) {
+        createContentViewAndroidDelegate();
         setContainerView(containerView);
-
         long windowNativePointer = windowAndroid.getNativePointer();
         assert windowNativePointer != 0;
-        mViewAndroid = new ViewAndroid(windowAndroid, getViewAndroidDelegate());
+        createViewAndroid(windowAndroid);
+
         long viewAndroidNativePointer = mViewAndroid.getNativePointer();
         assert viewAndroidNativePointer != 0;
 
@@ -648,13 +722,23 @@ public class ContentViewCore
         };
     }
 
+    @VisibleForTesting
+    void createContentViewAndroidDelegate() {
+        mViewAndroidDelegate = new ContentViewAndroidDelegate();
+    }
+
+    @VisibleForTesting
+    void createViewAndroid(WindowAndroid windowAndroid) {
+        mViewAndroid = new ViewAndroid(windowAndroid, mViewAndroidDelegate);
+    }
+
     /**
      * Sets a new container view for this {@link ContentViewCore}.
      *
-     * <p>WARNING: This is not a general purpose method and has been designed with WebView
-     * fullscreen in mind. Please be aware that it might not be appropriate for other use cases
-     * and that it has a number of limitations. For example the PopupZoomer only works with the
-     * container view with which this ContentViewCore has been initialized.
+     * <p>WARNING: This method can also be used to replace the existing container view,
+     * but you should only do it if you have a very good reason to. Replacing the
+     * container view has been designed to support fullscreen in the Webview so it
+     * might not be appropriate for other use cases.
      *
      * <p>This method only performs a small part of replacing the container view and
      * embedders are responsible for:
@@ -678,6 +762,7 @@ public class ContentViewCore
         mPositionObserver = new ViewPositionObserver(mContainerView);
         mContainerView.setWillNotDraw(false);
         mContainerView.setClickable(true);
+        mViewAndroidDelegate.updateCurrentContainerView();
         TraceEvent.end();
     }
 
@@ -696,7 +781,8 @@ public class ContentViewCore
         mContainerViewInternals = internalDispatcher;
     }
 
-    private void initPopupZoomer(Context context) {
+    @VisibleForTesting
+    void initPopupZoomer(Context context) {
         mPopupZoomer = new PopupZoomer(context);
         mPopupZoomer.setOnVisibilityChangedListener(new PopupZoomer.OnVisibilityChangedListener() {
             // mContainerView can change, but this OnVisibilityChangedListener can only be used