cc: Use impl-side painting in LTH context lost tests.

cc/trees/layer_tree_host_impl.cc

Index: cc/trees/layer_tree_host_impl.cc
diff --git a/cc/trees/layer_tree_host_impl.cc b/cc/trees/layer_tree_host_impl.cc
index afba687b2d8d3bcdc42ae39e27fdb42e95d1e043..3af5ba4cfe564ee567c02f565550b488042c55c3 100644
--- a/cc/trees/layer_tree_host_impl.cc
+++ b/cc/trees/layer_tree_host_impl.cc
@@ -1608,6 +1608,9 @@ void LayerTreeHostImpl::DidDrawAllLayers(const FrameData& frame) {
   // Once all layers have been drawn, pending texture uploads should no
   // longer block future uploads.
   resource_provider_->MarkPendingUploadsAsNonBlocking();
+
+  if (active_tree()->RequiresHighResToDraw())
+    active_tree()->ResetRequiresHighResToDraw();

[sohanjg, 2014/09/10 06:28:07]

we reset this on swap buffers too, but tests don't invoke it, so added it here.
Or we should remove the reset from swapbuffers ?

 }
 
 void LayerTreeHostImpl::FinishAllRendering() {
@@ -2062,6 +2065,12 @@ bool LayerTreeHostImpl::InitializeRenderer(
     return false;
 
   output_surface_ = output_surface.Pass();
+
+  // There will not be anything to draw here, so set high res
+  // to avoid checkerboards, typically when we are recovering
+  // from lost context.
+  active_tree_->SetRequiresHighResToDraw();
+
   have_valid_output_surface_ = true;
   resource_provider_ =
       ResourceProvider::Create(output_surface_.get(),