Implement Clone for Copy types.

components/compositing/compositor.rs

@@ -145,7 +145,7 @@ enum CompositionRequest {
     CompositeNow(CompositingReason),
 }
 
-#[derive(Copy, PartialEq, Debug)]
+#[derive(Clone, Copy, PartialEq, Debug)]
 enum ShutdownState {
     NotShuttingDown,
     ShuttingDown,

components/compositing/compositor_task.rs

@@ -95,7 +95,7 @@ impl ScriptListener for Box<CompositorProxy+'static+Send> {
 }
 
 /// Information about each layer that the compositor keeps.
-#[derive(Copy)]
+#[derive(Clone, Copy)]
 pub struct LayerProperties {
     pub pipeline_id: PipelineId,
     pub epoch: Epoch,

components/compositing/constellation.rs

@@ -170,7 +170,7 @@ pub struct SendableFrameTree {
     pub children: Vec<SendableFrameTree>,
 }
 
-#[derive(Copy)]
+#[derive(Clone, Copy)]
 enum ExitPipelineMode {
     Normal,
     Force,