Reland Allow one-copy and zero-copy task tile worker pools to use compressed textures.

cc/resources/resource_format.cc

 // Copyright 2013 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 "cc/resources/resource_format.h"
 
 #include "third_party/khronos/GLES2/gl2.h"
 #include "third_party/khronos/GLES2/gl2ext.h"
 
 namespace cc {
@@ skipping 83 matching lines @@
 gfx::BufferFormat BufferFormat(ResourceFormat format) {
   switch (format) {
     case BGRA_8888:
       return gfx::BufferFormat::BGRA_8888;
     case RED_8:
       return gfx::BufferFormat::R_8;
     case RGBA_4444:
       return gfx::BufferFormat::RGBA_4444;
     case RGBA_8888:
       return gfx::BufferFormat::RGBA_8888;
+    case ETC1:
+      return gfx::BufferFormat::ETC1;
     case ALPHA_8:
     case LUMINANCE_8:
     case RGB_565:
-    case ETC1:
     case LUMINANCE_F16:
       break;
   }
   NOTREACHED();
   return gfx::BufferFormat::RGBA_8888;
 }
 
+bool IsResourceFormatCompressed(ResourceFormat format) {
+  return format == ETC1;
+}
+
+bool DoesResourceFormatSupportAlpha(ResourceFormat format) {
+  switch (format) {
+    case RGBA_4444:
+    case RGBA_8888:
+    case BGRA_8888:
+    case ALPHA_8:
+      return true;
+    case LUMINANCE_8:
+    case RGB_565:
+    case ETC1:
+    case RED_8:
+    case LUMINANCE_F16:
+      return false;
+  }
+  NOTREACHED();
+  return false;
+}
+
 }  // namespace cc