cc: Adding support for RGBA_4444 tile textures

cc/layers/picture_layer_impl.cc

 // 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.
 
 #include "cc/layers/picture_layer_impl.h"
 
 #include <algorithm>
 
 #include "base/time/time.h"
 #include "cc/base/math_util.h"
@@ skipping 118 matching lines @@
     gfx::RectF texture_rect = gfx::RectF(texture_size);
     gfx::Rect quad_content_rect = rect;
     float contents_scale = contents_scale_x();
 
     scoped_ptr<PictureDrawQuad> quad = PictureDrawQuad::Create();
     quad->SetNew(shared_quad_state,
                  geometry_rect,
                  opaque_rect,
                  texture_rect,
                  texture_size,
-                 false,
+                 RGBA_8888,
                  quad_content_rect,
                  contents_scale,
                  draw_direct_to_backbuffer,
                  pile_);
     if (quad_sink->Append(quad.PassAs<DrawQuad>(), append_quads_data))
       append_quads_data->num_missing_tiles++;
     return;
   }
 
   AppendDebugBorderQuad(quad_sink, shared_quad_state, append_quads_data);
@@ skipping 91 matching lines @@
                      iter.texture_size(),
                      tile_version.contents_swizzled());
         draw_quad = quad.PassAs<DrawQuad>();
         break;
       }
       case ManagedTileState::TileVersion::PICTURE_PILE_MODE: {
         gfx::RectF texture_rect = iter.texture_rect();
         gfx::Rect opaque_rect = iter->opaque_rect();
         opaque_rect.Intersect(content_rect);
 
+        ResourceProvider* resource_provider =
+            layer_tree_impl()->resource_provider();
+        ResourceFormat format =
+            resource_provider->memory_efficient_texture_format();
         scoped_ptr<PictureDrawQuad> quad = PictureDrawQuad::Create();
         quad->SetNew(shared_quad_state,
                      geometry_rect,
                      opaque_rect,
                      texture_rect,
                      iter.texture_size(),
-                     // TODO(reveman): This assumes the renderer will use
-                     // GL_RGBA as format of temporary resource. The need
-                     // to swizzle should instead be determined by the
-                     // renderer.
-                     !PlatformColor::SameComponentOrder(GL_RGBA),
+                     format,
                      iter->content_rect(),
                      iter->contents_scale(),
                      draw_direct_to_backbuffer,
                      pile_);
         draw_quad = quad.PassAs<DrawQuad>();
         break;
       }
       case ManagedTileState::TileVersion::SOLID_COLOR_MODE: {
         scoped_ptr<SolidColorDrawQuad> quad = SolidColorDrawQuad::Create();
         quad->SetNew(shared_quad_state,
@@ skipping 809 matching lines @@
     coverage_tiles->Append(tile_data.release());
   }
   state->Set("coverage_tiles", coverage_tiles.release());
 }
 
 size_t PictureLayerImpl::GPUMemoryUsageInBytes() const {
   return tilings_->GPUMemoryUsageInBytes();
 }
 
 }  // namespace cc