Add 'Update LASTCHANGE' hook to DEPS

DEPS

 # This file contains dependencies for WebRTC that are not shared with Chromium.
 # If you wish to add a dependency that is present in Chromium's src/DEPS or a
 # directory from the Chromium checkout, you should add it to setup_links.py
 # instead.
 
 vars = {
   'chromium_git': 'https://chromium.googlesource.com',
   'chromium_revision': '5e821a778b85878bafcc8128f64333fd518c79a5',
 }
 
@@ skipping 234 matching lines @@
         'src/third_party/binutils/download.py',
     ],
   },
   {
     # Pull clang if needed or requested via GYP_DEFINES.
     # Note: On Win, this should run after win_toolchain, as it may use it.
     'name': 'clang',
     'pattern': '.',
     'action': ['python', 'src/tools/clang/scripts/update.py', '--if-needed'],
   },
+  {
+    # Update LASTCHANGE.
+    'name': 'lastchange',
+    'pattern': '.',
+    'action': ['python', 'src/build/util/lastchange.py',
+               '-o', 'src/build/util/LASTCHANGE'],
+  },
   # Pull GN binaries.
   {
     '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 130 matching lines @@
   },
 ]
 
 recursedeps = [
   # buildtools provides clang_format, libc++, and libc++abi.
   'src/buildtools',
   # android_tools manages the NDK.
   'src/third_party/android_tools',
 ]