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

cc/resources/resource_format.cc

Index: cc/resources/resource_format.cc
diff --git a/cc/resources/resource_format.cc b/cc/resources/resource_format.cc
index ba4e65d570a8c79f2128026f6f0c47ae641a4016..ec553d8acbc9b062795f1880f11dffca620dc862 100644
--- a/cc/resources/resource_format.cc
+++ b/cc/resources/resource_format.cc
@@ -101,10 +101,11 @@ gfx::BufferFormat BufferFormat(ResourceFormat format) {
       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;
   }
@@ -112,4 +113,26 @@ gfx::BufferFormat BufferFormat(ResourceFormat format) {
   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