Fix trailing whitespace in .cpp, .h, and .idl files (ex. Source/core)

Source/modules/webaudio/GainNode.cpp

 /*
  * Copyright (C) 2010, Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1.  Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 79 matching lines @@
 // As soon as we know the channel count of our input, we can lazily initialize.
 // Sometimes this may be called more than once with different channel counts, in which case we must safely
 // uninitialize and then re-initialize with the new channel count.
 void GainNode::checkNumberOfChannelsForInput(AudioNodeInput* input)
 {
     ASSERT(context()->isAudioThread() && context()->isGraphOwner());
 
     ASSERT(input && input == this->input(0));
     if (input != this->input(0))
         return;
-        
-    unsigned numberOfChannels = input->numberOfChannels();    
+
+    unsigned numberOfChannels = input->numberOfChannels();
 
     if (isInitialized() && numberOfChannels != output(0)->numberOfChannels()) {
         // We're already initialized but the channel count has changed.
         uninitialize();
     }
 
     if (!isInitialized()) {
         // This will propagate the channel count to any nodes connected further downstream in the graph.
         output(0)->setNumberOfChannels(numberOfChannels);
         initialize();
     }
 
     AudioNode::checkNumberOfChannelsForInput(input);
 }
 
 } // namespace WebCore
 
 #endif // ENABLE(WEB_AUDIO)