aw: Block child compositor if frame is not consumed by parent

android_webview/browser/shared_renderer_state.cc

Index: android_webview/browser/shared_renderer_state.cc
diff --git a/android_webview/browser/shared_renderer_state.cc b/android_webview/browser/shared_renderer_state.cc
index fb887a1b4110e2a208a39bf560e37da9a4a326ed..2286fcfdda4f07c90551c6009dd7fc1de6db03d2 100644
--- a/android_webview/browser/shared_renderer_state.cc
+++ b/android_webview/browser/shared_renderer_state.cc
@@ -134,6 +134,11 @@ void SharedRendererState::UpdateParentDrawConstraintsOnUIThread() {
   client_on_ui_->UpdateParentDrawConstraints();
 }
 
+bool SharedRendererState::HasDrawGLInput() const {
+  base::AutoLock lock(lock_);
+  return draw_gl_input_.get();
+}
+
 void SharedRendererState::SetDrawGLInput(scoped_ptr<DrawGLInput> input) {
   base::AutoLock lock(lock_);
   DCHECK(!draw_gl_input_.get());