Revert 116281 - Move paint aggregator and the completion callback factory.

ppapi/cpp/paint_aggregator.cc

 // Copyright (c) 2011 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.
 
 #include "ppapi/cpp/paint_aggregator.h"
 
 #include <algorithm>
 
 #include "ppapi/cpp/logging.h"
 
@@ skipping 259 matching lines @@
         outer = outer.Union(existing_rect);
       }
     }
     update_.paint_rects.clear();
     update_.paint_rects.push_back(inner);
     update_.paint_rects.push_back(outer);
   }
 }
 
 }  // namespace pp