Fix assorted issues with remote CoreAnimation

content/common/gpu/image_transport_surface_iosurface_mac.cc

Index: content/common/gpu/image_transport_surface_iosurface_mac.cc
diff --git a/content/common/gpu/image_transport_surface_iosurface_mac.cc b/content/common/gpu/image_transport_surface_iosurface_mac.cc
index cbae4a2612535fddbfa8dfaef2f01a5a1254b5e1..6181789399d68cf9b0e13a3e38a2a3586f5deef9 100644
--- a/content/common/gpu/image_transport_surface_iosurface_mac.cc
+++ b/content/common/gpu/image_transport_surface_iosurface_mac.cc
@@ -105,11 +105,10 @@ void IOSurfaceStorageProvider::FreeColorBufferStorage() {
   io_surface_id_ = 0;
 }
 
-uint64 IOSurfaceStorageProvider::GetSurfaceHandle() const {
-  return SurfaceHandleFromIOSurfaceID(io_surface_id_);
+void IOSurfaceStorageProvider::DiscardBackbuffer() {
 }
 
-void IOSurfaceStorageProvider::WillSwapBuffers() {
+uint64 IOSurfaceStorageProvider::SwapBuffersAndGetSurfaceHandle() {
   // The browser compositor will throttle itself, so we are free to unblock the
   // context immediately. Make sure that the browser is doing its throttling
   // appropriately by ensuring that the previous swap was acknowledged before
@@ -117,6 +116,8 @@ void IOSurfaceStorageProvider::WillSwapBuffers() {
   DCHECK(pending_swapped_surfaces_.empty());
   pending_swapped_surfaces_.push_back(io_surface_);
   transport_surface_->UnblockContextAfterPendingSwap();
+
+  return SurfaceHandleFromIOSurfaceID(io_surface_id_);
 }
 
 void IOSurfaceStorageProvider::CanFreeSwappedBuffer() {