WIP: Propagate SurfaceID up window tree hierarchy

cc/surfaces/surface_id_allocator.cc

Index: cc/surfaces/surface_id_allocator.cc
diff --git a/cc/surfaces/surface_id_allocator.cc b/cc/surfaces/surface_id_allocator.cc
index 330b3c3247299f95da6ef235c112e8759469adc9..dfd079d3e5636dcee55f4db758c4de974b924584 100644
--- a/cc/surfaces/surface_id_allocator.cc
+++ b/cc/surfaces/surface_id_allocator.cc
@@ -10,15 +10,15 @@
 
 namespace cc {
 
-SurfaceIdAllocator::SurfaceIdAllocator(uint32_t client_id)
-    : client_id_(client_id), next_id_(1u) {}
+SurfaceIdAllocator::SurfaceIdAllocator(const FrameSinkId& frame_sink_id)
+    : frame_sink_id_(frame_sink_id), next_id_(1u) {}
 
 SurfaceIdAllocator::~SurfaceIdAllocator() {
 }
 
 SurfaceId SurfaceIdAllocator::GenerateId() {
   uint64_t nonce = base::RandUint64();
-  SurfaceId id(client_id_, next_id_, nonce);
+  SurfaceId id(frame_sink_id_, next_id_, nonce);
   next_id_++;
   return id;
 }