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

cc/base/resource_id.h

Index: cc/base/resource_id.h
diff --git a/cc/base/resource_id.h b/cc/base/resource_id.h
new file mode 100644
index 0000000000000000000000000000000000000000..84d00ad8e592b8c10310a8e31b26cf0f93e886b5
--- /dev/null
+++ b/cc/base/resource_id.h
@@ -0,0 +1,16 @@
+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CC_BASE_RESOURCE_ID_H_
+#define CC_BASE_RESOURCE_ID_H_
+
+#include <stdint.h>
+
+namespace cc {
+
+using ResourceId = uint32_t;
+
+}  // namespace cc
+
+#endif  // CC_BASE_RESOURCE_ID_H_