gpu: support R16 GPUMemoryBuffer

gpu/command_buffer/tests/gl_gpu_memory_buffer_unittest.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 <GLES2/gl2.h>
 #include <GLES2/gl2chromium.h>
 #include <GLES2/gl2ext.h>
 #include <GLES2/gl2extchromium.h>
 #include <stdint.h>
 
@@ skipping 121 matching lines @@
         half_float_buffer[i + 3] = half_float_pixel[3];
       }
       return;
     }
     case gfx::BufferFormat::ATC:
     case gfx::BufferFormat::ATCIA:
     case gfx::BufferFormat::BGRX_8888:
     case gfx::BufferFormat::DXT1:
     case gfx::BufferFormat::DXT5:
     case gfx::BufferFormat::ETC1:
+    case gfx::BufferFormat::R_16:
     case gfx::BufferFormat::RG_88:
     case gfx::BufferFormat::RGBX_8888:
     case gfx::BufferFormat::UYVY_422:
     case gfx::BufferFormat::YVU_420:
     case gfx::BufferFormat::YUV_420_BIPLANAR:
       NOTREACHED();
       return;
   }
 
   NOTREACHED();
 }
 
 GLenum InternalFormat(gfx::BufferFormat format) {
   switch (format) {
     case gfx::BufferFormat::R_8:
       return GL_RED;
+    case gfx::BufferFormat::R_16:
+      return GL_R16_EXT;
     case gfx::BufferFormat::RG_88:
       return GL_RG;
     case gfx::BufferFormat::BGR_565:
       return GL_RGB;
     case gfx::BufferFormat::RGBA_4444:
     case gfx::BufferFormat::RGBA_8888:
       return GL_RGBA;
     case gfx::BufferFormat::BGRA_8888:
       return GL_BGRA_EXT;
     case gfx::BufferFormat::RGBA_F16:
@@ skipping 105 matching lines @@
                         GpuMemoryBufferTest,
                         ::testing::Values(gfx::BufferFormat::R_8,
                                           gfx::BufferFormat::BGR_565,
                                           gfx::BufferFormat::RGBA_4444,
                                           gfx::BufferFormat::RGBA_8888,
                                           gfx::BufferFormat::BGRA_8888,
                                           gfx::BufferFormat::RGBA_F16));
 
 }  // namespace gles2
 }  // namespace gpu