Allow task pools to reason about transparency.

cc/resources/resource_provider.h

 // Copyright 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.
 
 #ifndef CC_RESOURCES_RESOURCE_PROVIDER_H_
 #define CC_RESOURCES_RESOURCE_PROVIDER_H_
 
 #include <deque>
 #include <set>
 #include <string>
@@ skipping 76 matching lines @@
       BlockingTaskRunner* blocking_main_thread_task_runner,
       int highp_threshold_min,
       bool use_rgba_4444_texture_format,
       size_t id_allocation_chunk_size,
       const std::vector<unsigned>& use_image_texture_targets);
   ~ResourceProvider() override;
 
   void DidLoseOutputSurface() { lost_output_surface_ = true; }
 
   int max_texture_size() const { return max_texture_size_; }
-  ResourceFormat memory_efficient_texture_format() const {
-    return use_rgba_4444_texture_format_ ? RGBA_4444 : best_texture_format_;
-  }
+  ResourceFormat memory_efficient_texture_format(bool must_support_alpha) const;

[reveman, 2015/09/22 14:18:49]

Can we remove this function from ResourceProvider and instead pass the
use_rgba_4444_texture_format_ and future compressed texture settings directly to
the TileTaskWorkerPool impls? That's the only place we use this function so it
doesn't really need to be here. It just adds additional plumbing and makes the
code harder to follow imo.

[christiank, 2015/09/23 12:29:12]

Makes sense, fixed.

   ResourceFormat best_texture_format() const { return best_texture_format_; }
   ResourceFormat best_render_buffer_format() const {
     return best_render_buffer_format_;
   }
   ResourceFormat yuv_resource_format() const { return yuv_resource_format_; }
   bool use_sync_query() const { return use_sync_query_; }
   gpu::GpuMemoryBufferManager* gpu_memory_buffer_manager() {
     return gpu_memory_buffer_manager_;
   }
   size_t num_resources() const { return resources_.size(); }
@@ skipping 498 matching lines @@
   // A process-unique ID used for disambiguating memory dumps from different
   // resource providers.
   int tracing_id_;
 
   DISALLOW_COPY_AND_ASSIGN(ResourceProvider);
 };
 
 }  // namespace cc
 
 #endif  // CC_RESOURCES_RESOURCE_PROVIDER_H_