Migrate dartium_tools from chrome branch to dart repo

tools/dartium/generate_dart_vm_version.py

+import datetime
+import imp
+import os
+import subprocess
+import sys
+import time
+
+scriptpath = os.path.abspath(os.path.dirname(__file__))
+utils = imp.load_source('utils', os.path.join(scriptpath, '..', 'utils.py'))
+
+REVISION_FILE = 'src/chrome/browser/ui/webui/dartvm_revision.h'
+EXPIRATION_FILE = 'src/third_party/WebKit/Source/bindings/dart/ExpirationTimeSecsSinceEpoch.time_t'
+
+def updateFile(filename, content):
+  if os.path.exists(filename):
+    if file(filename, 'r').read() == content:
+      return
+  else:
+    dir = os.path.dirname(filename)
+    if not os.path.exists(dir):
+      os.makedirs(dir)
+  file(filename, 'w').write(content)
+
+def main():
+  dart_version = utils.GetVersion()
+  version_string = '#define DART_VM_REVISION "%s"\n' % dart_version.strip()
+
+  updateFile(REVISION_FILE, version_string)
+
+  expiration_date = datetime.date.today() + datetime.timedelta(weeks=12)
+  updateFile(EXPIRATION_FILE,
+             "%dLL\n" % time.mktime(expiration_date.timetuple()))
+
+if __name__ == '__main__':
+  main()