Use git workflow.

script/bootstrap

@@ -1,14 +1,19 @@
 #!/usr/bin/env python
 
+import errno
 import os
+import shutil
 import subprocess
 import sys
 
 
 SOURCE_ROOT = os.path.abspath(os.path.dirname(os.path.dirname(__file__)))
-DEPOT_TOOLS_DIR = os.path.join(SOURCE_ROOT, 'vendor', 'depot_tools')
+VENDOR_DIR = os.path.join(SOURCE_ROOT, 'vendor')
+DEPOT_TOOLS_DIR = os.path.join(VENDOR_DIR, 'depot_tools')
 DEPOT_TOOLS_URL = \
     'https://chromium.googlesource.com/chromium/tools/depot_tools.git'
+CHROMIUM_DIR = os.path.join(VENDOR_DIR, 'chromium')
+SRC_DIR = os.path.join(CHROMIUM_DIR, 'src')
 
 
 def main():
@@ -32,9 +37,28 @@ def main():
             if result:
                 return result
 
+    # Clean out old svn checkout.
+    if os.path.isdir(os.path.join(SRC_DIR, '.svn')):
+        rm_rf(SRC_DIR)
+
+    if not os.path.isdir(SRC_DIR):
+        os.chdir(CHROMIUM_DIR)
+        fetch = os.path.join(DEPOT_TOOLS_DIR, 'fetch.py')
+        result = subprocess.call([fetch, 'chromium'])
+        if result:
+            return result;
+
     update = os.path.join(SOURCE_ROOT, 'script', 'update')
     return subprocess.call([sys.executable, update])
 
 
+def rm_rf(path):
+    try:
+        shutil.rmtree(path)
+    except OSError as e:
+        if e.errno != errno.ENOENT:
+            raise
+
+
 if __name__ == '__main__':
     sys.exit(main())

script/update

@@ -16,7 +16,7 @@ CHROMIUMCONTENT_DESTINATION_DIR = os.path.join(SRC_DIR, 'chromiumcontent')
 
 
 def main():
-    return (write_dot_gclient() or
+    return (checkout_version() or
             gclient_sync() or
             apply_patches() or
             copy_chromiumcontent_files() or
@@ -24,21 +24,22 @@ def main():
             install_win_tool_wrapper())
 
 
-def write_dot_gclient():
-    template = os.path.join(CHROMIUM_DIR, '.gclient.in')
-    destination = os.path.join(CHROMIUM_DIR, '.gclient')
-    version = chromium_version()
-    with open(template) as t:
-        with open(destination, 'w') as d:
-            for line in t:
-                d.write(line.replace('{{VERSION}}', version))
-
-
 def chromium_version():
     with open(os.path.join(SOURCE_ROOT, 'VERSION')) as f:
         return f.readline().strip()
 
 
+def checkout_version():
+    os.chdir(SRC_DIR)
+    result = subprocess.call(['git', 'fetch', '--tags'])
+    if result:
+        return result
+    result = subprocess.call(['git', 'checkout',
+                              'refs/tags/{0}'.format(chromium_version())])
+    if result:
+        return result
+
+
 def gclient_sync():
     gclient = os.path.join(DEPOT_TOOLS_DIR, 'gclient.py')
     os.chdir(CHROMIUM_DIR)