cc: Remove support for disabling non-root render surfaces.

cc/trees/layer_tree_impl.cc

 // Copyright 2011 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/trees/layer_tree_impl.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <algorithm>
@@ skipping 1003 matching lines @@
   render_surface_list_.clear();
 
   if (layer_list_.empty())
     return false;
 
   {
     base::ElapsedTimer timer;
     TRACE_EVENT2(
         "cc", "LayerTreeImpl::UpdateDrawProperties::CalculateDrawProperties",
         "IsActive", IsActiveTree(), "SourceFrameNumber", source_frame_number_);
-    // TODO(crbug.com/692780): Remove this option entirely once this get to
-    // stable and proves it works.
-    bool can_render_to_separate_surface = true;
-
     // We verify visible rect calculations whenever we verify clip tree
     // calculations except when this function is explicitly passed a flag asking
     // us to skip it.
     LayerTreeHostCommon::CalcDrawPropsImplInputs inputs(
         layer_list_[0], DrawViewportSize(),
         layer_tree_host_impl_->DrawTransform(), device_scale_factor(),
         current_page_scale_factor(), PageScaleLayer(),
         InnerViewportScrollLayer(), OuterViewportScrollLayer(),
         elastic_overscroll()->Current(IsActiveTree()),
         OverscrollElasticityLayer(), resource_provider()->max_texture_size(),
-        can_render_to_separate_surface,
         settings().layer_transforms_should_scale_layer_contents,
         &render_surface_list_, &property_trees_);
     LayerTreeHostCommon::CalculateDrawProperties(&inputs);
     if (const char* client_name = GetClientNameForMetrics()) {
       UMA_HISTOGRAM_COUNTS(
           base::StringPrintf(
               "Compositing.%s.LayerTreeImpl.CalculateDrawPropertiesUs",
               client_name),
           timer.Elapsed().InMicroseconds());
       UMA_HISTOGRAM_COUNTS_100(
@@ skipping 1043 matching lines @@
 
 void LayerTreeImpl::ResetAllChangeTracking() {
   layers_that_should_push_properties_.clear();
   // Iterate over all layers, including masks.
   for (auto& layer : *layers_)
     layer->ResetChangeTracking();
   property_trees_.ResetAllChangeTracking();
 }
 
 }  // namespace cc