cc: Only add surface ID to embedded_surfaces if fallback does not match

cc/layers/surface_layer_impl.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 "cc/layers/surface_layer_impl.h"
 
 #include <stdint.h>
 
 #include "base/trace_event/trace_event_argument.h"
 #include "cc/debug/debug_colors.h"
@@ skipping 48 matching lines @@
   SurfaceLayerImpl* layer_impl = static_cast<SurfaceLayerImpl*>(layer);
   layer_impl->SetPrimarySurfaceInfo(primary_surface_info_);
   layer_impl->SetFallbackSurfaceInfo(fallback_surface_info_);
   layer_impl->SetStretchContentToFillBounds(stretch_content_to_fill_bounds_);
 }
 
 void SurfaceLayerImpl::AppendQuads(RenderPass* render_pass,
                                    AppendQuadsData* append_quads_data) {
   AppendRainbowDebugBorder(render_pass);
   SharedQuadState* common_shared_quad_state = nullptr;
-  auto* primary = CreateSurfaceDrawQuad(
-      render_pass, SurfaceDrawQuadType::PRIMARY, primary_surface_info_,
-      &append_quads_data->embedded_surfaces, &common_shared_quad_state);
+  auto* primary =
+      CreateSurfaceDrawQuad(render_pass, SurfaceDrawQuadType::PRIMARY,
+                            primary_surface_info_, &common_shared_quad_state);
   // Emitting a fallback SurfaceDrawQuad is unnecessary if the primary and
   // fallback surface Ids match.
-  if (primary && fallback_surface_info_.id() != primary_surface_info_.id()) {
+  bool needs_fallback =
+      fallback_surface_info_.id() != primary_surface_info_.id();
+  if (primary && needs_fallback) {
+    // Add the primary surface ID as a dependency.
+    append_quads_data->embedded_surfaces.push_back(primary_surface_info_.id());
     // We can use the same SharedQuadState as the primary SurfaceDrawQuad if
     // we don't need a different transform on the fallback.
     bool use_common_shared_quad_state =
         !stretch_content_to_fill_bounds_ &&
         primary_surface_info_.device_scale_factor() ==
             fallback_surface_info_.device_scale_factor();
     primary->fallback_quad = CreateSurfaceDrawQuad(
         render_pass, SurfaceDrawQuadType::FALLBACK, fallback_surface_info_,
-        nullptr /* embedded_surfaces */,
         use_common_shared_quad_state ? &common_shared_quad_state : nullptr);
   }
 }
 
 SurfaceDrawQuad* SurfaceLayerImpl::CreateSurfaceDrawQuad(
     RenderPass* render_pass,
     SurfaceDrawQuadType surface_draw_quad_type,
     const SurfaceInfo& surface_info,
-    std::vector<SurfaceId>* embedded_surfaces,
     SharedQuadState** common_shared_quad_state) {
   if (!surface_info.is_valid())
     return nullptr;
 
   gfx::Rect quad_rect(surface_info.size_in_pixels());
   gfx::Rect visible_quad_rect =
       draw_properties().occlusion_in_content_space.GetUnoccludedContentRect(
           gfx::Rect(bounds()));
 
   float layer_to_content_scale_x, layer_to_content_scale_y;
@@ skipping 29 matching lines @@
     PopulateScaledSharedQuadState(shared_quad_state, layer_to_content_scale_x,
                                   layer_to_content_scale_y);
   }
   if (common_shared_quad_state)
     *common_shared_quad_state = shared_quad_state;
 
   SurfaceDrawQuad* surface_draw_quad =
       render_pass->CreateAndAppendDrawQuad<SurfaceDrawQuad>();
   surface_draw_quad->SetNew(shared_quad_state, quad_rect, visible_quad_rect,
                             surface_info.id(), surface_draw_quad_type, nullptr);
-  if (embedded_surfaces)
-    embedded_surfaces->push_back(surface_info.id());
 
   return surface_draw_quad;
 }
 
 void SurfaceLayerImpl::GetDebugBorderProperties(SkColor* color,
                                                 float* width) const {
   *color = DebugColors::SurfaceLayerBorderColor();
   *width = DebugColors::SurfaceLayerBorderWidth(
       layer_tree_impl() ? layer_tree_impl()->device_scale_factor() : 1);
 }
@@ skipping 90 matching lines @@
   dict->SetString("surface_id", primary_surface_info_.id().ToString());
   dict->SetString("fallback_surface_id",
                   fallback_surface_info_.id().ToString());
 }
 
 const char* SurfaceLayerImpl::LayerTypeAsString() const {
   return "cc::SurfaceLayerImpl";
 }
 
 }  // namespace cc