cc::ResourcePool - Re-use larger resources for smaller requests

ui/compositor/compositor.cc

 // Copyright (c) 2012 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 "ui/compositor/compositor.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 #include <deque>
@@ skipping 172 matching lines @@
       uint32_t target = context_factory_->GetImageTextureTarget(format, usage);
       settings.renderer_settings
           .buffer_to_texture_target_map[std::make_pair(usage, format)] = target;
     }
   }
 
   settings.gpu_memory_policy.bytes_limit_when_visible = 512 * 1024 * 1024;
   settings.gpu_memory_policy.priority_cutoff_when_visible =
       gpu::MemoryAllocation::CUTOFF_ALLOW_NICE_TO_HAVE;
 
+  settings.renderer_settings.disallow_non_exact_resource_reuse =

[danakj, 2017/05/04 21:48:37]

This won't affect layout tests fwiw, but it's fine cuz it could apply for other
types of pixel tests.

But I don't see how the flag is getting to the renderer compositor.

[ericrk, 2017/05/05 23:18:38]

Yup, missed the other half of this. Added it in.

+      command_line->HasSwitch(cc::switches::kDisallowNonExactResourceReuse);
+
   base::TimeTicks before_create = base::TimeTicks::Now();
 
   animation_host_ = cc::AnimationHost::CreateMainInstance();
 
   cc::LayerTreeHost::InitParams params;
   params.client = this;
   params.task_graph_runner = context_factory_->GetTaskGraphRunner();
   params.settings = &settings;
   params.main_task_runner = task_runner_;
   params.mutator_host = animation_host_.get();
@@ skipping 393 matching lines @@
 void Compositor::TimeoutLocks() {
   // Make a copy, we're going to cause |active_locks_| to become
   // empty.
   std::vector<CompositorLock*> locks = active_locks_;
   for (auto* lock : locks)
     lock->TimeoutLock();
   DCHECK(active_locks_.empty());
 }
 
 }  // namespace ui