Allow task pools to reason about transparency.

cc/tiles/tile_manager_perftest.cc

Index: cc/tiles/tile_manager_perftest.cc
diff --git a/cc/tiles/tile_manager_perftest.cc b/cc/tiles/tile_manager_perftest.cc
index 1542233bc1c80d0a612d69e222c920395c70acfa..3e1f3bff6368d4238b9551c34d133013bdeb5985 100644
--- a/cc/tiles/tile_manager_perftest.cc
+++ b/cc/tiles/tile_manager_perftest.cc
@@ -62,9 +62,12 @@ class FakeTileTaskRunnerImpl : public TileTaskRunner, public TileTaskClient {
     }
     completed_tasks_.clear();
   }
-  ResourceFormat GetResourceFormat() const override { return RGBA_8888; }
-  bool GetResourceRequiresSwizzle() const override {
-    return !PlatformColor::SameComponentOrder(GetResourceFormat());
+  ResourceFormat GetResourceFormat(bool must_support_alpha) const override {
+    return RGBA_8888;
+  }
+  bool GetResourceRequiresSwizzle(bool must_support_alpha) const override {
+    return !PlatformColor::SameComponentOrder(
+        GetResourceFormat(must_support_alpha));
   }
 
   // Overridden from TileTaskClient: