Add R_8 GPU memory buffers format.

content/common/gpu/gpu_memory_buffer_factory_shared_memory.cc

Index: content/common/gpu/gpu_memory_buffer_factory_shared_memory.cc
diff --git a/content/common/gpu/gpu_memory_buffer_factory_shared_memory.cc b/content/common/gpu/gpu_memory_buffer_factory_shared_memory.cc
index 790fcab9f8ae4bfcda1daba8d4b1638a446cdb03..4cbfc4a16c5636305a85e3e23f71691a2ce5b44c 100644
--- a/content/common/gpu/gpu_memory_buffer_factory_shared_memory.cc
+++ b/content/common/gpu/gpu_memory_buffer_factory_shared_memory.cc
@@ -23,9 +23,9 @@ void GpuMemoryBufferFactorySharedMemory::
     GetSupportedGpuMemoryBufferConfigurations(
         std::vector<Configuration>* configurations) {
   const Configuration supported_configurations[] = {
-    { gfx::GpuMemoryBuffer::RGBA_8888, gfx::GpuMemoryBuffer::MAP },
-    { gfx::GpuMemoryBuffer::BGRA_8888, gfx::GpuMemoryBuffer::MAP }
-  };
+      {gfx::GpuMemoryBuffer::R_8, gfx::GpuMemoryBuffer::MAP},
+      {gfx::GpuMemoryBuffer::RGBA_8888, gfx::GpuMemoryBuffer::MAP},
+      {gfx::GpuMemoryBuffer::BGRA_8888, gfx::GpuMemoryBuffer::MAP}};
   configurations->assign(
       supported_configurations,
       supported_configurations + arraysize(supported_configurations));