RendererCompositorFrameSink should handle local surface id allocation

ui/android/delegated_frame_host_android.cc

Index: ui/android/delegated_frame_host_android.cc
diff --git a/ui/android/delegated_frame_host_android.cc b/ui/android/delegated_frame_host_android.cc
index 46b1df3fada90a333b6db132ad82383b5ac93d0f..bef401b236b190fb302b759fe5b870d6c9cb7a25 100644
--- a/ui/android/delegated_frame_host_android.cc
+++ b/ui/android/delegated_frame_host_android.cc
@@ -11,7 +11,6 @@
 #include "cc/layers/surface_layer.h"
 #include "cc/output/compositor_frame.h"
 #include "cc/output/copy_output_result.h"
-#include "cc/surfaces/local_surface_id_allocator.h"
 #include "cc/surfaces/surface.h"
 #include "cc/surfaces/surface_id.h"
 #include "cc/surfaces/surface_manager.h"
@@ -63,7 +62,6 @@ DelegatedFrameHostAndroid::DelegatedFrameHostAndroid(
   DCHECK(view_);
   DCHECK(client_);
 
-  local_surface_id_allocator_.reset(new cc::LocalSurfaceIdAllocator());
   surface_manager_->RegisterFrameSinkId(frame_sink_id_);
   CreateNewCompositorFrameSinkSupport();
 }
@@ -80,11 +78,13 @@ DelegatedFrameHostAndroid::FrameData::FrameData() = default;
 DelegatedFrameHostAndroid::FrameData::~FrameData() = default;
 
 void DelegatedFrameHostAndroid::SubmitCompositorFrame(
+    cc::LocalSurfaceId local_surface_id,

[Fady Samuel, 2017/03/15 12:05:48]

const cc::LocalSurfaceId&

[Saman Sami, 2017/03/16 18:33:08]

Done.

     cc::CompositorFrame frame) {
   cc::RenderPass* root_pass = frame.render_pass_list.back().get();
   gfx::Size surface_size = root_pass->output_rect.size();
 
   if (!current_frame_ || surface_size != current_frame_->surface_size ||

[Fady Samuel, 2017/03/15 12:05:48]

This can be simplified once you move the conditions to
RendererCompositorFrameSink...

If the local_surface_id has changed then 

1. DestroyDelegatedContent();
2. content_layer_ = CreateSurfaceLayer(...);
3. AddChild(content_layer_);

[Saman Sami, 2017/03/16 18:33:08]

Done.

+      current_frame_->local_surface_id != local_surface_id ||
       current_frame_->top_controls_height !=
           frame.metadata.top_controls_height ||
       current_frame_->top_controls_shown_ratio !=
@@ -101,8 +101,7 @@ void DelegatedFrameHostAndroid::SubmitCompositorFrame(
     DCHECK(!current_frame_);
 
     current_frame_ = base::MakeUnique<FrameData>();
-    current_frame_->local_surface_id =
-        local_surface_id_allocator_->GenerateId();
+    current_frame_->local_surface_id = local_surface_id;
     current_frame_->surface_size = surface_size;
     current_frame_->top_controls_height = frame.metadata.top_controls_height;
     current_frame_->top_controls_shown_ratio =