Remove app_installer code.

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 318 matching lines @@
     'src/third_party/mingw-w64/mingw/bin':
       Var('chromium_git') + '/native_client/deps/third_party/mingw-w64/mingw/bin.git' + '@' + '3cc8b140b883a9fe4986d12cfd46c16a093d3527',
 
     # Dependencies used by libjpeg-turbo
     'src/third_party/yasm/binaries':
      Var('chromium_git') + '/chromium/deps/yasm/binaries.git' + '@' + '52f9b3f4b0aa06da24ef8b123058bb61ee468881',
 
     # Binaries for nacl sdk.
     'src/third_party/nacl_sdk_binaries':
      Var('chromium_git') + '/chromium/deps/nacl_sdk_binaries.git' + '@' + '759dfca03bdc774da7ecbf974f6e2b84f43699a5',
-
-    # Omaha code for src/app_installer/.
-    'src/third_party/omaha/src/omaha':
-     Var('chromium_git') + '/external/omaha.git' + '@' + '098c7a3d157218dab4eed595e8f2fbe5a20a0bae',
   },
   'ios': {
     'src/ios/third_party/gcdwebserver/src':
      Var('chromium_git') + '/external/github.com/swisspol/GCDWebServer.git' + '@' + '18889793b75d7ee593d62ac88997caad850acdb6',
 
     'src/third_party/google_toolbox_for_mac/src':
       Var('chromium_git') + '/external/google-toolbox-for-mac.git' + '@' + Var('google_toolbox_for_mac_revision'),
 
     'src/third_party/nss':
      Var('chromium_git') + '/chromium/deps/nss.git' + '@' + Var('nss_revision'),
@@ skipping 408 matching lines @@
     # corresponding .py files have already been deleted.
     'name': 'remove_stale_pyc_files',
     'pattern': 'src/tools/.*\\.py',
     'action': [
         'python',
         'src/tools/remove_stale_pyc_files.py',
         'src/tools',
     ],
   },
 ]