Remove obsolete override "ios_extra_version_path".

DEPS

 # This file is used to manage the dependencies of the Chromium src repo. It is
 # used by gclient to determine what version of each dependency to check out, and
 # where.
 #
 # For more information, please refer to the official documentation:
 #   https://sites.google.com/a/chromium.org/dev/developers/how-tos/get-the-code
 #
 # When adding a new dependency, please update the top-level .gitignore file
 # to list the dependency's destination directory.
 #
@@ skipping 635 matching lines @@
   },
   {
     # Update LASTCHANGE.blink.
     'name': 'lastchange_blink',
     'pattern': '.',
     'action': ['python', 'src/build/util/lastchange.py',
                '--git-hash-only',
                '-s', 'src/third_party/WebKit',
                '-o', 'src/build/util/LASTCHANGE.blink'],
   },
-  {
-    # Update CANARY_VERSION.
-    'name': 'ios_canary_version',
-    'pattern': '.',
-    'action': ['python', 'src/ios/build/util/canary_version.py',
-               '-o', 'src/ios/build/util/CANARY_VERSION'],
-  },
   # Pull GN binaries. This needs to be before running GYP below.
   {
     'name': 'gn_win',
     'pattern': '.',
     'action': [ 'download_from_google_storage',
                 '--no_resume',
                 '--platform=win32',
                 '--no_auth',
                 '--bucket', 'chromium-gn',
                 '-s', 'src/buildtools/win/gn.exe.sha1',
@@ skipping 181 matching lines @@
     'pattern': '\\.sha1',
     'action': ['python', 'src/third_party/instrumented_libraries/scripts/download_binaries.py'],
   },
   {
     # A change to a .gyp, .gypi, or to GYP itself should run the generator.
     'name': 'gyp',
     'pattern': '.',
     'action': ['python', 'src/build/gyp_chromium'],
   },
 ]