Rewrite scrollable layers using multiple layers.

Remove PlatformBridge::updateLayers and instead call layersDraw from
ChromeClientAndroid during a requested sync.

Instead of LayerAndroid having knowledge of scrolling pictures, use multiple
layers (background, mask, foreground).

Update navigation to use the new structure.  Always record nodes in absolute,
unscrolled coordinates.  Do not track layers unless the node has a composited
layer and a last child.  Check for composited parents when adding to tracked
layers as well.

TODO:
* developer.android.com doesn't completely work with navigation due to some
  nodes being clipped out.
* BaseLayerAndroid needs to be able to operate with a matrix other than
  identity.
* nested fixed position elements do not draw correctly.
* nested overflow layers haven't been tested.

Change-Id: I0e2bd37612341e8884d68153ab36194cb2dc1eeb

1 files changed, 4 insertions, 1 deletions

diff --git a/WebCore/platform/graphics/android/BaseLayerAndroid.cpp b/WebCore/platform/graphics/android/BaseLayerAndroid.cpp
index f139eeb..996b272 100644
--- a/WebCore/platform/graphics/android/BaseLayerAndroid.cpp
+++ b/WebCore/platform/graphics/android/BaseLayerAndroid.cpp
@@ -92,7 +92,10 @@ void BaseLayerAndroid::setContent(const PictureSet& src)
     android::Mutex::Autolock lock(m_drawLock);
 #endif
     m_content.set(src);
-    setSize(src.width(), src.height());
+    // FIXME: We cannot set the size of the base layer because it will screw up
+    // the matrix used.  We need to fix matrix computation for the base layer
+    // and then we can set the size.
+    // setSize(src.width(), src.height());
 }
 
 void BaseLayerAndroid::setExtra(SkPicture& src)