gpu: support R16 GPUMemoryBuffer

ui/gl/test/gl_image_test_support.cc

 // Copyright 2015 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 "ui/gl/test/gl_image_test_support.h"
 
 #include <vector>
 
 #include "ui/gfx/half_float.h"
 #include "ui/gl/gl_implementation.h"
@@ skipping 42 matching lines @@
                                               const uint8_t color[4],
                                               uint8_t* data) {
   switch (format) {
     case gfx::BufferFormat::R_8:
     case gfx::BufferFormat::RG_88:
       DCHECK_EQ(0, plane);
       for (int y = 0; y < height; ++y) {
         memset(&data[y * stride], color[0], width);
       }
       return;
+    case gfx::BufferFormat::R_16:
+      DCHECK_EQ(0, plane);
+      uint16_t red;
+      red = (uint16_t)color[0] << 8;

[reveman, 2017/06/14 17:47:21]

nit: "uint16_t red = static_cast<uint16_t>(color[0] << 8)" although I don't
think a temporary variable is really needed here. doing "row[x] =
static_cast<uint16_t>(color[0] << 8)" at l.70 is fine imo.

[riju_, 2017/06/20 13:21:31]

Done.

+      for (int y = 0; y < height; ++y) {
+        uint16_t* row = reinterpret_cast<uint16_t*>(data + y * stride);
+        for (int x = 0; x < width; ++x) {
+          row[x] = red;
+        }
+      }
+      return;
     case gfx::BufferFormat::BGR_565:
       DCHECK_EQ(0, plane);
       for (int y = 0; y < height; ++y) {
         for (int x = 0; x < width; ++x) {
           *reinterpret_cast<uint16_t*>(&data[y * stride + x * 2]) =
               ((color[2] >> 3) << 11) | ((color[1] >> 2) << 5) |
               (color[0] >> 3);
         }
       }
       return;
@@ skipping 120 matching lines @@
     case gfx::BufferFormat::ETC1:
     case gfx::BufferFormat::RGBA_4444:
     case gfx::BufferFormat::UYVY_422:
       NOTREACHED();
       return;
   }
   NOTREACHED();
 }
 
 }  // namespace gl