Turn off computation of the interest rect in cc in synchronized paint mode.

cc/trees/layer_tree_host_pixeltest_readback.cc

Index: cc/trees/layer_tree_host_pixeltest_readback.cc
diff --git a/cc/trees/layer_tree_host_pixeltest_readback.cc b/cc/trees/layer_tree_host_pixeltest_readback.cc
index d7f0a92b1ee64196943d98230efdf45bb881425f..d87bb6e81a52ef403f68085df97bdaa9e5094c16 100644
--- a/cc/trees/layer_tree_host_pixeltest_readback.cc
+++ b/cc/trees/layer_tree_host_pixeltest_readback.cc
@@ -458,9 +458,9 @@ class LayerTreeHostReadbackDeviceScalePixelTest
  protected:
   LayerTreeHostReadbackDeviceScalePixelTest()
       : device_scale_factor_(1.f),
-        white_client_(SK_ColorWHITE),
-        green_client_(SK_ColorGREEN),
-        blue_client_(SK_ColorBLUE) {}
+        white_client_(SK_ColorWHITE, gfx::Size(200, 200)),
+        green_client_(SK_ColorGREEN, gfx::Size(200, 200)),
+        blue_client_(SK_ColorBLUE, gfx::Size(200, 200)) {}
 
   void InitializeSettings(LayerTreeSettings* settings) override {
     // Cause the device scale factor to be inherited by contents scales.