Make cc::CompositorFrames movable [Part 1 of 2]

cc/output/compositor_frame.cc

Index: cc/output/compositor_frame.cc
diff --git a/cc/output/compositor_frame.cc b/cc/output/compositor_frame.cc
index f096a387b5cc82feb88cc12cd32cfcfa7e0b1d2f..82479cf3b43ab363fb4cd1b458754f10e8da1429 100644
--- a/cc/output/compositor_frame.cc
+++ b/cc/output/compositor_frame.cc
@@ -8,12 +8,10 @@ namespace cc {
 
 CompositorFrame::CompositorFrame() {}
 
+CompositorFrame::CompositorFrame(CompositorFrame&& other) = default;
+
 CompositorFrame::~CompositorFrame() {}
 
-void CompositorFrame::AssignTo(CompositorFrame* target) {
-  target->delegated_frame_data = std::move(delegated_frame_data);
-  target->gl_frame_data = std::move(gl_frame_data);
-  target->metadata = metadata;
-}
+CompositorFrame& CompositorFrame::operator=(CompositorFrame&& other) = default;
 
 }  // namespace cc