RendererCompositorFrameSink should handle local surface id allocation

content/browser/frame_host/render_widget_host_view_child_frame.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/browser/frame_host/render_widget_host_view_child_frame.h"
 
 #include <algorithm>
 #include <utility>
 #include <vector>
 
@@ skipping 40 matching lines @@
     RenderWidgetHost* widget_host)
     : host_(RenderWidgetHostImpl::From(widget_host)),
       frame_sink_id_(
           base::checked_cast<uint32_t>(widget_host->GetProcess()->GetID()),
           base::checked_cast<uint32_t>(widget_host->GetRoutingID())),
       next_surface_sequence_(1u),
       last_compositor_frame_sink_id_(0),
       current_surface_scale_factor_(1.f),
       frame_connector_(nullptr),
       weak_factory_(this) {
-  id_allocator_.reset(new cc::LocalSurfaceIdAllocator());
   GetSurfaceManager()->RegisterFrameSinkId(frame_sink_id_);
   CreateCompositorFrameSinkSupport();
 }
 
 RenderWidgetHostViewChildFrame::~RenderWidgetHostViewChildFrame() {
   ResetCompositorFrameSinkSupport();
   if (GetSurfaceManager())
     GetSurfaceManager()->InvalidateFrameSinkId(frame_sink_id_);
 }
 
@@ skipping 272 matching lines @@
 void RenderWidgetHostViewChildFrame::DidReceiveCompositorFrameAck() {
   if (!host_)
     return;
   host_->Send(new ViewMsg_ReclaimCompositorResources(
       host_->GetRoutingID(), last_compositor_frame_sink_id_,
       true /* is_swap_ack */, cc::ReturnedResourceArray()));
 }
 
 void RenderWidgetHostViewChildFrame::ProcessCompositorFrame(
     uint32_t compositor_frame_sink_id,
+    const cc::LocalSurfaceId& local_surface_id,
     cc::CompositorFrame frame) {
   // If the renderer changed its frame sink, reset the
   // CompositorFrameSinkSupport to avoid returning stale resources.
   if (compositor_frame_sink_id != last_compositor_frame_sink_id_) {
     ResetCompositorFrameSinkSupport();
     CreateCompositorFrameSinkSupport();
     last_compositor_frame_sink_id_ = compositor_frame_sink_id;
-    local_surface_id_ = cc::LocalSurfaceId();
   }
 
-  gfx::Size new_frame_size = frame.render_pass_list.back()->output_rect.size();
-  float new_scale_factor = frame.metadata.device_scale_factor;
-  bool allocated_new_local_surface_id = false;
-  if (!local_surface_id_.is_valid() ||
-      new_frame_size != current_surface_size_ ||
-      new_scale_factor != current_surface_scale_factor_) {
-    local_surface_id_ = id_allocator_->GenerateId();
-    current_surface_size_ = frame.render_pass_list.back()->output_rect.size();
-    current_surface_scale_factor_ = frame.metadata.device_scale_factor;
-    allocated_new_local_surface_id = true;
+  current_surface_size_ = frame.render_pass_list.back()->output_rect.size();
+  current_surface_scale_factor_ = frame.metadata.device_scale_factor;
+
+  support_->SubmitCompositorFrame(local_surface_id, std::move(frame));
+  has_frame_ = true;
+
+  if (local_surface_id_ != local_surface_id || HasEmbedderChanged()) {
+    local_surface_id_ = local_surface_id;
+    SendSurfaceInfoToEmbedder();
   }
 
-  support_->SubmitCompositorFrame(local_surface_id_, std::move(frame));
-  has_frame_ = true;
-
-  if (allocated_new_local_surface_id || HasEmbedderChanged())
-    SendSurfaceInfoToEmbedder();
   ProcessFrameSwappedCallbacks();
 }
 
 void RenderWidgetHostViewChildFrame::SendSurfaceInfoToEmbedder() {
   cc::SurfaceSequence sequence =
       cc::SurfaceSequence(frame_sink_id_, next_surface_sequence_++);
   cc::SurfaceManager* manager = GetSurfaceManager();
   cc::SurfaceId surface_id(frame_sink_id_, local_surface_id_);
   // The renderer process will satisfy this dependency when it creates a
   // SurfaceLayer.
   manager->RequireSequence(surface_id, sequence);
   cc::SurfaceInfo surface_info(surface_id, current_surface_scale_factor_,
                                current_surface_size_);
   SendSurfaceInfoToEmbedderImpl(surface_info, sequence);
 }
 
 void RenderWidgetHostViewChildFrame::SendSurfaceInfoToEmbedderImpl(
     const cc::SurfaceInfo& surface_info,
     const cc::SurfaceSequence& sequence) {
   frame_connector_->SetChildFrameSurface(surface_info, sequence);
 }
 
 void RenderWidgetHostViewChildFrame::OnSwapCompositorFrame(
     uint32_t compositor_frame_sink_id,
+    const cc::LocalSurfaceId& local_surface_id,
     cc::CompositorFrame frame) {
   TRACE_EVENT0("content",
                "RenderWidgetHostViewChildFrame::OnSwapCompositorFrame");
   last_scroll_offset_ = frame.metadata.root_scroll_offset;
   if (!frame_connector_)
     return;
-  ProcessCompositorFrame(compositor_frame_sink_id, std::move(frame));
+  ProcessCompositorFrame(compositor_frame_sink_id, local_surface_id,
+                         std::move(frame));
 }
 
 void RenderWidgetHostViewChildFrame::ProcessFrameSwappedCallbacks() {
   // We only use callbacks once, therefore we make a new list for registration
   // before we start, and discard the old list entries when we are done.
   FrameSwappedCallbackList process_callbacks;
   process_callbacks.swap(frame_swapped_callbacks_);
   for (std::unique_ptr<base::Closure>& callback : process_callbacks)
     callback->Run();
 }
@@ skipping 282 matching lines @@
                                                       frame_sink_id_);
   }
   support_.reset();
 }
 
 bool RenderWidgetHostViewChildFrame::HasEmbedderChanged() {
   return false;
 }
 
 }  // namespace content