Introduce GN config files.

DEPS

 # Copyright 2014 Google Inc. All Rights Reserved.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
 # You may obtain a copy of the License at
 #
 #     http://www.apache.org/licenses/LICENSE-2.0
 #
 # Unless required by applicable law or agreed to in writing, software
 # distributed under the License is distributed on an "AS IS" BASIS,
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
 vars = {
   # Name of the directory to which the repository is pulled in.
   "root": "src",
   # This is expected to be Python 2.7 from depot_tools.
   "python_path": "python",
 
   "chromium_git": "https://chromium.googlesource.com",
   "buildtools_revision": "a7cc7a3e21a061975b33dcdcd81a9716ba614c3c",
+  "icu_revision": "9cd2828740572ba6f694b9365236a8356fd06147",
 }
 
 deps = {
   Var("root") + "/buildtools":
-    Var('chromium_git') + '/chromium/buildtools.git' + '@' +  Var('buildtools_revision'),
+    (Var('chromium_git') + '/chromium/buildtools.git' + '@' +
+     Var('buildtools_revision')),
+  Var("root") + "/third_party/icu":
+    Var('chromium_git') + '/chromium/deps/icu.git' + '@' + Var('icu_revision'),
 }
 
 include_rules = [
 ]
 
 hooks = [
   {
     "name": "run_gitdeps",
     "pattern": ".",
     "action": [Var("python_path"),
@@ skipping 18 matching lines @@
     # Update the Windows toolchain if necessary.
     "name": "win_toolchain",
     "pattern": ".",
     "action": [Var("python_path"),
                Var("root") + "/build/vs_toolchain.py",
                "update",
     ],
   },
   # TODO(veranika): run GN here.
   {
+    "name": "lastchange",
+    "pattern": ".",
+    "action": ["python", "src/build/util/lastchange.py",
+               "-o", "src/build/util/LASTCHANGE"],
+  },
+  {
     "name": "download_clang_format",
     "pattern": ".",
     "action": ["download_from_google_storage",
                "--no_resume",
                "--platform=win32",
                "--no_auth",
                "--bucket", "chromium-clang-format",
                "-s", Var("root") + "/buildtools/win/clang-format.exe.sha1",
     ],
   },
 ]