Fix SafeAdd and SafeMultiply

BUG=145648,145544


Review URL: https://chromiumcodereview.appspot.com/10916165

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@155478 0039d316-1c4b-4281-b951-d872f2087c98
  RenderbufferManager::RenderbufferInfo* GetRenderbufferInfo(
      GLuint client_id) {
    RenderbufferManager::RenderbufferInfo* info =
        renderbuffer_manager()->GetRenderbufferInfo(client_id);
    return info;
  }

  RenderbufferManager::RenderbufferInfo* GetRenderbufferInfo(
      GLuint client_id) {
    RenderbufferManager::RenderbufferInfo* info =
        renderbuffer_manager()->GetRenderbufferInfo(client_id);
    return info;
  }
