Add a flag to disable partial raster in renderer

cc/test/fake_picture_layer_tiling_client.cc

Index: cc/test/fake_picture_layer_tiling_client.cc
diff --git a/cc/test/fake_picture_layer_tiling_client.cc b/cc/test/fake_picture_layer_tiling_client.cc
index 52849077a43ec79bee055dec5209fafdc1c92a3d..649ad13296280a8da4239b49c05f84a036df364a 100644
--- a/cc/test/fake_picture_layer_tiling_client.cc
+++ b/cc/test/fake_picture_layer_tiling_client.cc
@@ -17,7 +17,8 @@ FakePictureLayerTilingClient::FakePictureLayerTilingClient()
       raster_source_(FakeDisplayListRasterSource::CreateInfiniteFilled()),
       twin_set_(nullptr),
       twin_tiling_(nullptr),
-      has_valid_tile_priorities_(true) {}
+      has_valid_tile_priorities_(true),
+      partial_raster_enabled_(false) {}
 
 FakePictureLayerTilingClient::FakePictureLayerTilingClient(
     ResourceProvider* resource_provider)
@@ -30,7 +31,8 @@ FakePictureLayerTilingClient::FakePictureLayerTilingClient(
       raster_source_(FakeDisplayListRasterSource::CreateInfiniteFilled()),
       twin_set_(nullptr),
       twin_tiling_(nullptr),
-      has_valid_tile_priorities_(true) {}
+      has_valid_tile_priorities_(true),
+      partial_raster_enabled_(false) {}
 
 FakePictureLayerTilingClient::~FakePictureLayerTilingClient() {
 }
@@ -73,4 +75,8 @@ bool FakePictureLayerTilingClient::RequiresHighResToDraw() const {
   return false;
 }
 
+bool FakePictureLayerTilingClient::IsPartialRasterEnabled() const {
+  return partial_raster_enabled_;
+}
+
 }  // namespace cc