Bug 859683 - Allow scrolling in full-screen mode if and only if the full-screen element is the document element. r=wesj

mobile/android/base/GeckoApp.java

@@ -36,6 +36,7 @@ import org.mozilla.gecko.background.announcements.AnnouncementsBroadcastService;
 import org.mozilla.gecko.db.BrowserDB;
 import org.mozilla.gecko.favicons.Favicons;
 import org.mozilla.gecko.gfx.BitmapUtils;
+import org.mozilla.gecko.gfx.FullScreenState;
 import org.mozilla.gecko.gfx.Layer;
 import org.mozilla.gecko.gfx.LayerView;
 import org.mozilla.gecko.gfx.PluginLayer;
@@ -564,13 +565,14 @@ public abstract class GeckoApp
                 // Local ref to layerView for thread safety
                 LayerView layerView = mLayerView;
                 if (layerView != null) {
-                    layerView.setFullScreen(true);
+                    layerView.setFullScreenState(message.getBoolean("rootElement")
+                            ? FullScreenState.ROOT_ELEMENT : FullScreenState.NON_ROOT_ELEMENT);
                 }
             } else if (event.equals("DOMFullScreen:Stop")) {
                 // Local ref to layerView for thread safety
                 LayerView layerView = mLayerView;
                 if (layerView != null) {
-                    layerView.setFullScreen(false);
+                    layerView.setFullScreenState(FullScreenState.NONE);
                 }
             } else if (event.equals("Permissions:Data")) {
                 String host = message.getString("host");

mobile/android/base/gfx/FullScreenState.java

@@ -0,0 +1,12 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.gfx;
+
+public enum FullScreenState {
+    NONE,
+    ROOT_ELEMENT,
+    NON_ROOT_ELEMENT
+}

mobile/android/base/gfx/GeckoLayerClient.java

@@ -801,8 +801,8 @@ class GeckoLayerClient implements LayerView.Listener, PanZoomTarget
 
     /** Implementation of PanZoomTarget */
     @Override
-    public boolean isFullScreen() {
-        return mView.isFullScreen();
+    public FullScreenState getFullScreenState() {
+        return mView.getFullScreenState();
     }
 
     /** Implementation of PanZoomTarget */

mobile/android/base/gfx/JavaPanZoomController.java

@@ -469,8 +469,11 @@ class JavaPanZoomController
             return false;
 
         case TOUCHING:
-            // Don't allow panning if there is an element in full-screen mode. See bug 775511.
-            if ((mTarget.isFullScreen() && !mSubscroller.scrolling()) || panDistance(event) < PAN_THRESHOLD) {
+            // Don't allow panning if there is a non-root element in full-screen mode. See bug 775511 and bug 859683.
+            if (mTarget.getFullScreenState() == FullScreenState.NON_ROOT_ELEMENT && !mSubscroller.scrolling()) {
+                return false;
+            }
+            if (panDistance(event) < PAN_THRESHOLD) {
                 return false;
             }
             cancelTouch();
@@ -1173,7 +1176,7 @@ class JavaPanZoomController
 
     @Override
     public boolean onScale(SimpleScaleGestureDetector detector) {
-        if (mTarget.isFullScreen())
+        if (mTarget.getFullScreenState() != FullScreenState.NONE)
             return false;
 
         if (mState != PanZoomState.PINCHING)

mobile/android/base/gfx/LayerRenderer.java

@@ -504,9 +504,11 @@ public class LayerRenderer implements Tabs.OnTabsChangedListener {
             // Run through pre-render tasks
             runRenderTasks(mTasks, false, mFrameStartTime);
 
-            if (!mPageContext.fuzzyEquals(mLastPageContext) && !mView.isFullScreen()) {
+            boolean hideScrollbars = (mView.getFullScreenState() == FullScreenState.NON_ROOT_ELEMENT);
+            if (!mPageContext.fuzzyEquals(mLastPageContext) && !hideScrollbars) {
                 // The viewport or page changed, so show the scrollbars again
-                // as per UX decision. Don't do this if we're in full-screen mode though.
+                // as per UX decision. Don't do this if we're disabling scrolling due to
+                // full-screen mode though.
                 mVertScrollLayer.unfade();
                 mHorizScrollLayer.unfade();
                 mFadeRunnable.scheduleStartFade(ScrollbarLayer.FADE_DELAY);

mobile/android/base/gfx/LayerView.java

@@ -64,7 +64,7 @@ public class LayerView extends FrameLayout implements Tabs.OnTabsChangedListener
     /* Must be a PAINT_xxx constant */
     private int mPaintState;
     private int mBackgroundColor;
-    private boolean mFullScreen;
+    private FullScreenState mFullScreenState;
 
     private SurfaceView mSurfaceView;
     private TextureView mTextureView;
@@ -109,6 +109,7 @@ public class LayerView extends FrameLayout implements Tabs.OnTabsChangedListener
         mGLController = GLController.getInstance(this);
         mPaintState = PAINT_START;
         mBackgroundColor = Color.WHITE;
+        mFullScreenState = FullScreenState.NONE;
 
         mTouchInterceptors = new ArrayList<TouchEventInterceptor>();
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.ICE_CREAM_SANDWICH) {
@@ -692,12 +693,16 @@ public class LayerView extends FrameLayout implements Tabs.OnTabsChangedListener
         GeckoAccessibility.onLayerViewFocusChanged(this, gainFocus);
     }
 
-    public void setFullScreen(boolean fullScreen) {
-        mFullScreen = fullScreen;
+    public void setFullScreenState(FullScreenState state) {
+        mFullScreenState = state;
     }
 
     public boolean isFullScreen() {
-        return mFullScreen;
+        return mFullScreenState != FullScreenState.NONE;
+    }
+
+    public FullScreenState getFullScreenState() {
+        return mFullScreenState;
     }
 
     @Override

mobile/android/base/gfx/PanZoomTarget.java

@@ -13,7 +13,7 @@ import android.graphics.RectF;
 public interface PanZoomTarget {
     public ImmutableViewportMetrics getViewportMetrics();
     public ZoomConstraints getZoomConstraints();
-    public boolean isFullScreen();
+    public FullScreenState getFullScreenState();
     public RectF getMaxMargins();
 
     public void setAnimationTarget(ImmutableViewportMetrics viewport);

mobile/android/base/moz.build

@@ -199,6 +199,7 @@ gbjar.sources += [
     'gfx/DisplayPortMetrics.java',
     'gfx/DrawTimingQueue.java',
     'gfx/FloatSize.java',
+    'gfx/FullScreenState.java',
     'gfx/GeckoLayerClient.java',
     'gfx/GLController.java',
     'gfx/ImmutableViewportMetrics.java',

mobile/android/chrome/content/browser.js

@@ -346,12 +346,19 @@ var BrowserApp = {
       });
     }, false);
 
-    window.addEventListener("mozfullscreenchange", function() {
+    window.addEventListener("mozfullscreenchange", function(e) {
+      // This event gets fired on the document and its entire ancestor chain
+      // of documents. When enabling fullscreen, it is fired on the top-level
+      // document first and goes down; when disabling the order is reversed
+      // (per spec). This means the last event on enabling will be for the innermost
+      // document, which will have mozFullScreenElement set correctly.
+      let doc = e.target;
       sendMessageToJava({
-        type: document.mozFullScreen ? "DOMFullScreen:Start" : "DOMFullScreen:Stop"
+        type: doc.mozFullScreen ? "DOMFullScreen:Start" : "DOMFullScreen:Stop",
+        rootElement: (doc.mozFullScreen && doc.mozFullScreenElement == doc.documentElement)
       });
 
-      if (document.mozFullScreen)
+      if (doc.mozFullScreen)
         showFullScreenWarning();
     }, false);