android: Expose content locks in RenderWidgetHostViewAndroid

content/browser/renderer_host/render_widget_host_view_android.cc

Index: content/browser/renderer_host/render_widget_host_view_android.cc
diff --git a/content/browser/renderer_host/render_widget_host_view_android.cc b/content/browser/renderer_host/render_widget_host_view_android.cc
index 44d060a63ead8d96cda20647e83152460a04d979..36c4e2a5251f916d6aad2d449cbbee43c2bce151 100644
--- a/content/browser/renderer_host/render_widget_host_view_android.cc
+++ b/content/browser/renderer_host/render_widget_host_view_android.cc
@@ -144,6 +144,7 @@ RenderWidgetHostViewAndroid::RenderWidgetHostViewAndroid(
                                         widget_host->GetProcess()->GetID(),
                                         widget_host->GetRoutingID()) != NULL),
       frame_evictor_(new DelegatedFrameEvictor(this)),
+      frame_locked_(false),
       using_delegated_renderer_(CommandLine::ForCurrentProcess()->HasSwitch(
                                     switches::kEnableDelegatedRenderer) &&
                                 !CommandLine::ForCurrentProcess()->HasSwitch(
@@ -411,11 +412,15 @@ void RenderWidgetHostViewAndroid::LockResources() {
   DCHECK(HasValidFrame());
   DCHECK(host_);
   DCHECK(!host_->is_hidden());
+  DCHECK(!frame_locked_);
   frame_evictor_->LockFrame();
+  frame_locked_ = true;
 }
 
 void RenderWidgetHostViewAndroid::UnlockResources() {
   DCHECK(HasValidFrame());
+  DCHECK(frame_locked_);
+  frame_locked_ = false;
   frame_evictor_->UnlockFrame();
 }
 
@@ -849,6 +854,18 @@ void RenderWidgetHostViewAndroid::OnSwapCompositorFrame(
 
     DCHECK(frame->delegated_frame_data);
     DCHECK(!frame->delegated_frame_data->render_pass_list.empty());
+    if (frame_locked_) {
+      base::Closure ack_callback =
+          base::Bind(&RenderWidgetHostViewAndroid::SendDelegatedFrameAck,
+                     weak_ptr_factory_.GetWeakPtr(),
+                     output_surface_id);
+
+      if (host_->is_hidden())
+        ack_callback.Run();
+      else
+        ack_callbacks_.push(ack_callback);
+      return;
+    }
 
     cc::RenderPass* root_pass =
         frame->delegated_frame_data->render_pass_list.back();
@@ -1381,6 +1398,8 @@ void RenderWidgetHostViewAndroid::OnDetachCompositor() {
 }
 
 void RenderWidgetHostViewAndroid::OnLostResources() {
+  if (frame_locked_)
+    UnlockResources();
   if (texture_layer_.get())
     texture_layer_->SetIsDrawable(false);
   if (delegated_renderer_layer_.get())