Tiling priorities in Android Webview.

android_webview/browser/browser_view_renderer.cc

Index: android_webview/browser/browser_view_renderer.cc
diff --git a/android_webview/browser/browser_view_renderer.cc b/android_webview/browser/browser_view_renderer.cc
index fd00b6be6b701a1c054c305d7ccadf9ae3f1890b..cd315c1e4eed3bc2d4c1aa8de415bd9be15cec26 100644
--- a/android_webview/browser/browser_view_renderer.cc
+++ b/android_webview/browser/browser_view_renderer.cc
@@ -258,14 +258,19 @@ bool BrowserViewRenderer::OnDrawHardware(jobject java_canvas) {
   draw_gl_input->width = width_;
   draw_gl_input->height = height_;
 
-  gfx::Transform transform;
   gfx::Size surface_size(width_, height_);
   gfx::Rect viewport(surface_size);
-  // TODO(boliu): Should really be |last_on_draw_global_visible_rect_|.
-  // See crbug.com/372073.
+
   gfx::Rect clip = viewport;
+
+  if (shared_renderer_state_->IsParentDrawConstraintsDirty()) {

[boliu, 2014/07/16 17:25:10]

Don't bother with dirty. Copying 16 floats isn't that expensive

[hush (inactive), 2014/07/16 20:45:32]

Done.

+    parent_transform_ = shared_renderer_state_->ParentTransform();
+    parent_clip_ = shared_renderer_state_->ParentClip();
+    shared_renderer_state_->SetParentDrawConstraintsDirty(false);
+  }
+
   scoped_ptr<cc::CompositorFrame> frame = compositor_->DemandDrawHw(
-      surface_size, transform, viewport, clip);
+      surface_size, parent_transform_, viewport, clip, parent_clip_);
   if (!frame.get())
     return false;