cc: Avoid extra flush calls to Skia GrContext

cc/raster/gpu_rasterizer.cc

Index: cc/raster/gpu_rasterizer.cc
diff --git a/cc/raster/gpu_rasterizer.cc b/cc/raster/gpu_rasterizer.cc
index b8ad86212e49765b14f819051c285b9ef62002a9..41f615110660df13665f914dab3862ae5745f8c0 100644
--- a/cc/raster/gpu_rasterizer.cc
+++ b/cc/raster/gpu_rasterizer.cc
@@ -79,7 +79,7 @@ void GpuRasterizer::RasterizeSource(
 
     SkMultiPictureDraw multi_picture_draw;
     multi_picture_draw.add(sk_surface->getCanvas(), picture.get());
-    multi_picture_draw.draw(msaa_sample_count_ > 0);
+    multi_picture_draw.draw(true);
     write_lock->ReleaseSkSurface();
   }
 }