Add R_8 GPU memory buffers format.

cc/test/test_gpu_memory_buffer_manager.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/test/test_gpu_memory_buffer_manager.h"
 
 #include "base/logging.h"
 #include "ui/gfx/gpu_memory_buffer.h"
 
 namespace cc {
 namespace {
 
 size_t StrideInBytes(size_t width, gfx::GpuMemoryBuffer::Format format) {
   switch (format) {
     case gfx::GpuMemoryBuffer::ATCIA:
     case gfx::GpuMemoryBuffer::DXT5:
       return width;
     case gfx::GpuMemoryBuffer::ATC:
     case gfx::GpuMemoryBuffer::DXT1:
     case gfx::GpuMemoryBuffer::ETC1:
       DCHECK_EQ(width % 2, 0U);
       return width / 2;
+    case gfx::GpuMemoryBuffer::R_8:
+      return (width + 3) & ~0x3;
     case gfx::GpuMemoryBuffer::RGBA_8888:
     case gfx::GpuMemoryBuffer::RGBX_8888:
     case gfx::GpuMemoryBuffer::BGRA_8888:
       return width * 4;
   }
 
   NOTREACHED();
   return 0;
 }
 
@@ skipping 70 matching lines @@
     ClientBuffer buffer) {
   return reinterpret_cast<gfx::GpuMemoryBuffer*>(buffer);
 }
 
 void TestGpuMemoryBufferManager::SetDestructionSyncPoint(
     gfx::GpuMemoryBuffer* buffer,
     uint32 sync_point) {
 }
 
 }  // namespace cc