Rename cc::ResourceProvider::ResourceId to cc::ResourceId and move it to its own file.

cc/resources/transferable_resource.h

Index: cc/resources/transferable_resource.h
diff --git a/cc/resources/transferable_resource.h b/cc/resources/transferable_resource.h
index 03b47e616c8bf3965057ecc428b0af85c9bd39b9..0c09d2ef9c3aa2908d2a82aa34f7aba010258bb8 100644
--- a/cc/resources/transferable_resource.h
+++ b/cc/resources/transferable_resource.h
@@ -10,6 +10,7 @@
 #include "base/basictypes.h"
 #include "cc/base/cc_export.h"
 #include "cc/resources/resource_format.h"
+#include "cc/resources/resource_id.h"
 #include "gpu/command_buffer/common/mailbox_holder.h"
 #include "ui/gfx/geometry/size.h"
 
@@ -28,7 +29,7 @@ struct CC_EXPORT TransferableResource {
   static void ReturnResources(const TransferableResourceArray& input,
                               ReturnedResourceArray* output);
 
-  unsigned id;
+  ResourceId id;
   ResourceFormat format;
   uint32 filter;
   gfx::Size size;