Move NumberOfPlanesForGpuMemoryBufferFormat to gfx

ui/gfx/buffer_format_util.cc

Index: ui/gfx/buffer_format_util.cc
diff --git a/ui/gfx/buffer_format_util.cc b/ui/gfx/buffer_format_util.cc
new file mode 100644
index 0000000000000000000000000000000000000000..61cf26066719d095e131c66e44ba9a3c72ef9dc6
--- /dev/null
+++ b/ui/gfx/buffer_format_util.cc
@@ -0,0 +1,31 @@
+// 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/gfx/buffer_format_util.h"
+
+#include "base/logging.h"
+
+namespace gfx {
+
+size_t NumberOfPlanesForBufferFormat(BufferFormat format) {
+  switch (format) {
+    case BufferFormat::ATC:
+    case BufferFormat::ATCIA:
+    case BufferFormat::DXT1:
+    case BufferFormat::DXT5:
+    case BufferFormat::ETC1:
+    case BufferFormat::R_8:
+    case BufferFormat::RGBA_4444:
+    case BufferFormat::RGBA_8888:
+    case BufferFormat::RGBX_8888:
+    case BufferFormat::BGRA_8888:
+      return 1;
+    case BufferFormat::YUV_420:
+      return 3;
+  }
+  NOTREACHED();
+  return 0;
+}
+
+}  // namespace gfx