Make the GUID upper case (so Visual Studio won't try to correct...

third_party/ffmpeg/ffmpeg.gyp

 # Copyright (c) 2009 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.
 
 {
   'includes': [
     '../../build/common.gypi',
   ],
   'target_defaults': {
     'conditions': [
@@ skipping 81 matching lines @@
               'action': ['python', '<@(_inputs)', '-o', '<(PRODUCT_DIR)/lib', '<@(RULE_INPUT_PATH)'],
               'message': 'Generating import libraries',
             },
           ],
         }],
       ],
     },
     {
       'target_name': 'ffmpeg_binaries',
       'type': 'none',
-      'msvs_guid': '4E4070E1-EFD9-4ef1-8634-3960956F6F10',
+      'msvs_guid': '4E4070E1-EFD9-4EF1-8634-3960956F6F10',
       'conditions': [
         ['OS=="win"', {
           'sources': [
             'binaries/avcodec-52.dll',
             'binaries/avformat-52.dll',
             'binaries/avutil-50.dll',
             'binaries/pthreadGC2.dll',
           ],
           'dependencies': ['../../build/win/system.gyp:cygwin'],
           'rules': [
             {
               'rule_name': 'copy_binaries',
               'extension': 'dll',
               'inputs': [
                 'copy_binaries.sh',
               ],
               'outputs': [
                 '<(PRODUCT_DIR)/<(RULE_INPUT_NAME)',
               ],
               'action': ['./copy_binaries.sh', '"<@(RULE_INPUT_PATH)"', '"<@(PRODUCT_DIR)/<@(RULE_INPUT_NAME)"'],
               'message': 'Copying binaries...',
             },
           ],
         }],
       ],
     },
   ],
 }