Split surface id and simplify connecting to surfaces service

mojo/converters/surfaces/surfaces_type_converters.cc

Index: mojo/converters/surfaces/surfaces_type_converters.cc
diff --git a/mojo/converters/surfaces/surfaces_type_converters.cc b/mojo/converters/surfaces/surfaces_type_converters.cc
index 1a6ab99985ce13a79235bdf08bc9e50c07b9eafa..6a315e8ab01ae45d4bf77f1e07b6740c292a2b94 100644
--- a/mojo/converters/surfaces/surfaces_type_converters.cc
+++ b/mojo/converters/surfaces/surfaces_type_converters.cc
@@ -16,6 +16,7 @@
 #include "cc/quads/texture_draw_quad.h"
 #include "cc/quads/tile_draw_quad.h"
 #include "cc/quads/yuv_video_draw_quad.h"
+#include "cc/surfaces/surface_id_allocator.h"
 #include "mojo/converters/geometry/geometry_type_converters.h"
 
 namespace mojo {
@@ -194,14 +195,18 @@ bool ConvertDrawQuad(const QuadPtr& input,
 SurfaceIdPtr TypeConverter<SurfaceIdPtr, cc::SurfaceId>::Convert(
     const cc::SurfaceId& input) {
   SurfaceIdPtr id(SurfaceId::New());
-  id->id = input.id;
+  id->local = static_cast<uint32_t>(input.id);
+  id->id_namespace = cc::SurfaceIdAllocator::NamespaceForId(input);
   return id.Pass();
 }
 
 // static
 cc::SurfaceId TypeConverter<cc::SurfaceId, SurfaceIdPtr>::Convert(
     const SurfaceIdPtr& input) {
-  return cc::SurfaceId(input->id);
+  uint64_t packed_id = input->id_namespace;
+  packed_id <<= 32ull;
+  packed_id |= input->local;
+  return cc::SurfaceId(packed_id);
 }
 
 // static