aw: Fallback delegated composite

android_webview/browser/hardware_renderer.cc

Index: android_webview/browser/hardware_renderer.cc
diff --git a/android_webview/browser/hardware_renderer.cc b/android_webview/browser/hardware_renderer.cc
index 4aff9c7ac9bf5a14994e05ea90279e842eec17c1..5e711ff1f35594bfdb4453ed6616da2f95d22017 100644
--- a/android_webview/browser/hardware_renderer.cc
+++ b/android_webview/browser/hardware_renderer.cc
@@ -140,7 +140,7 @@ void HardwareRenderer::DidBeginMainFrame() {
 
 void HardwareRenderer::CommitFrame() {
   scroll_offset_ = shared_renderer_state_->GetScrollOffset();
-  if (committed_frame_.get()) {
+  if (committed_frame_.get() && !shared_renderer_state_->ForceCommit()) {
     TRACE_EVENT_INSTANT0("android_webview",
                          "EarlyOut_PreviousFrameUnconsumed",
                          TRACE_EVENT_SCOPE_THREAD);
@@ -206,6 +206,11 @@ void HardwareRenderer::DrawGL(bool stencil_enabled,
     DLOG(WARNING) << "EGLContextChanged";
 
   SetFrameData();
+  if (shared_renderer_state_->ForceCommit()) {
+    CommitFrame();
+    SetFrameData();

[boliu, 2014/10/15 18:01:25]

Hmm, my guess is it doesn't like having 2 frames shoved into the layer at once??
That would really suck and make this more complicated...

[hush (inactive), 2014/10/15 18:17:30]

you committed frame data twice. I don't know what that does.
Supposedly your fallback tick's frame data is most recent, and you can just drop
the previous frames' data.

+  }
+
   gfx::Transform transform(gfx::Transform::kSkipInitialization);
   transform.matrix().setColMajorf(draw_info->transform);
   transform.Translate(scroll_offset_.x(), scroll_offset_.y());