Add R_8 GPU memory buffers format.

gpu/command_buffer/tests/gl_gpu_memory_buffer_unittest.cc

Index: gpu/command_buffer/tests/gl_gpu_memory_buffer_unittest.cc
diff --git a/gpu/command_buffer/tests/gl_gpu_memory_buffer_unittest.cc b/gpu/command_buffer/tests/gl_gpu_memory_buffer_unittest.cc
index 052bd3d23974db832b3710827e19e0bbab0938e0..9d9dd4fcfbda2b76573d5e126582186a241ac675 100644
--- a/gpu/command_buffer/tests/gl_gpu_memory_buffer_unittest.cc
+++ b/gpu/command_buffer/tests/gl_gpu_memory_buffer_unittest.cc
@@ -80,6 +80,9 @@ SHADER(
 std::vector<uint8> GetTexturePixel(const gfx::GpuMemoryBuffer::Format format) {
   std::vector<uint8> pixel;
   switch (format) {
+    case gfx::GpuMemoryBuffer::R_8:
+      pixel.push_back(255u);
+      return pixel;
     case gfx::GpuMemoryBuffer::RGBA_8888:
       pixel.push_back(255u);
       pixel.push_back(0u);
@@ -110,6 +113,7 @@ std::vector<uint8> GetFramebufferPixel(
     const gfx::GpuMemoryBuffer::Format format) {
   std::vector<uint8> pixel;
   switch (format) {
+    case gfx::GpuMemoryBuffer::R_8:
     case gfx::GpuMemoryBuffer::RGBA_8888:
     case gfx::GpuMemoryBuffer::BGRA_8888:
       pixel.push_back(255u);
@@ -133,6 +137,8 @@ std::vector<uint8> GetFramebufferPixel(
 
 GLenum InternalFormat(gfx::GpuMemoryBuffer::Format format) {
   switch (format) {
+    case gfx::GpuMemoryBuffer::R_8:
+      return GL_R8;
     case gfx::GpuMemoryBuffer::RGBA_8888:
       return GL_RGBA;
     case gfx::GpuMemoryBuffer::BGRA_8888:
@@ -155,6 +161,9 @@ GLenum InternalFormat(gfx::GpuMemoryBuffer::Format format) {
 
 // An end to end test that tests the whole GpuMemoryBuffer lifecycle.
 TEST_P(GpuMemoryBufferTest, Lifecycle) {
+  ASSERT_TRUE((GetParam() != gfx::GpuMemoryBuffer::R_8) ||

[reveman, 2015/04/08 02:57:28]

We should consider adding a histogram to find out how common it is that this is
missing in the wild. This patch does that:
https://codereview.chromium.org/1068133002

+              gl_.GetCapabilities().texture_rg);
+
   GLuint texture_id = 0;
   glGenTextures(1, &texture_id);
   ASSERT_NE(0u, texture_id);
@@ -240,7 +249,8 @@ TEST_P(GpuMemoryBufferTest, Lifecycle) {
 
 INSTANTIATE_TEST_CASE_P(GpuMemoryBufferTests,
                         GpuMemoryBufferTest,
-                        ::testing::Values(gfx::GpuMemoryBuffer::RGBA_8888,
+                        ::testing::Values(gfx::GpuMemoryBuffer::R_8,
+                                          gfx::GpuMemoryBuffer::RGBA_8888,
                                           gfx::GpuMemoryBuffer::BGRA_8888));
 
 }  // namespace gles2