Aura: Have ui::Layer implement WebKit::WebExternalTextureLayerClient

ui/compositor/layer.cc

Index: ui/compositor/layer.cc
diff --git a/ui/compositor/layer.cc b/ui/compositor/layer.cc
index f45fd8471ce856aeb92ca0bb815003694cf64945..423459b0e33164ac2a13b57b23061ca96072ce24 100644
--- a/ui/compositor/layer.cc
+++ b/ui/compositor/layer.cc
@@ -311,10 +311,14 @@ void Layer::SetExternalTexture(Texture* texture) {
     WebKit::WebLayer new_layer;
     if (layer_updated_externally_) {
       WebKit::WebExternalTextureLayer texture_layer =
-          WebKit::WebExternalTextureLayer::create();
+          WebKit::WebExternalTextureLayer::create(this);
       texture_layer.setFlipped(texture_->flipped());
       new_layer = texture_layer;
     } else {
+      // Tell the compositor to clear references to the old texture.
+      WebKit::WebExternalTextureLayer texture_layer =
+          web_layer_.to<WebKit::WebExternalTextureLayer>();
+      texture_layer.willModifyTexture();
       new_layer = WebKit::WebContentLayer::create(this);
     }
     if (parent_) {
@@ -435,6 +439,16 @@ void Layer::paintContents(WebKit::WebCanvas* web_canvas,
     delegate_->OnPaintLayer(&canvas);
 }
 
+unsigned Layer::prepareTexture(WebKit::WebTextureUpdater& /* updater */) {
+  DCHECK(layer_updated_externally_);
+  return texture_->texture_id();
+}
+
+WebKit::WebGraphicsContext3D* Layer::context() {
+  DCHECK(layer_updated_externally_);
+  return texture_->HostContext3D();
+}
+
 void Layer::SetForceRenderSurface(bool force) {
   if (force_render_surface_ == force)
     return;
@@ -634,10 +648,8 @@ void Layer::RecomputeDrawsContentAndUVRect() {
     web_layer_.setBounds(ConvertSizeToPixel(this, bounds_.size()));
   } else {
     DCHECK(texture_);
-    unsigned int texture_id = texture_->texture_id();
     WebKit::WebExternalTextureLayer texture_layer =
         web_layer_.to<WebKit::WebExternalTextureLayer>();
-    texture_layer.setTextureId(should_draw ? texture_id : 0);
 
     gfx::Size texture_size;
     if (scale_content_)