Reusing base::IdType<...> to implement SurfaceId.

cc/quads/surface_draw_quad.cc

Index: cc/quads/surface_draw_quad.cc
diff --git a/cc/quads/surface_draw_quad.cc b/cc/quads/surface_draw_quad.cc
index 655158152a6ee5e795d13d9ed3586c41cec7d574..5757dc23a79b5c68c1f0ad2ada58854f4b888996 100644
--- a/cc/quads/surface_draw_quad.cc
+++ b/cc/quads/surface_draw_quad.cc
@@ -10,8 +10,9 @@
 
 namespace cc {
 
-SurfaceDrawQuad::SurfaceDrawQuad() {
-}
+SurfaceDrawQuad::SurfaceDrawQuad() {}
+
+SurfaceDrawQuad::~SurfaceDrawQuad() {}
 
 void SurfaceDrawQuad::SetNew(const SharedQuadState* shared_quad_state,
                              const gfx::Rect& rect,
@@ -41,7 +42,7 @@ const SurfaceDrawQuad* SurfaceDrawQuad::MaterialCast(const DrawQuad* quad) {
 }
 
 void SurfaceDrawQuad::ExtendValue(base::trace_event::TracedValue* value) const {
-  value->SetInteger("surface_id", surface_id.id);
+  value->SetInteger("surface_id", surface_id.GetUnsafeValue());
 }