Adds bot_update to depot_tools.

infra/recipe_modules/rietveld/api.py

Index: infra/recipe_modules/rietveld/api.py
diff --git a/infra/recipe_modules/rietveld/api.py b/infra/recipe_modules/rietveld/api.py
new file mode 100644
index 0000000000000000000000000000000000000000..a80c93af6059247117b873da9f83caa873721f5f
--- /dev/null
+++ b/infra/recipe_modules/rietveld/api.py
@@ -0,0 +1,45 @@
+# Copyright 2013 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import urlparse
+
+from recipe_engine import recipe_api
+
+class RietveldApi(recipe_api.RecipeApi):
+  def calculate_issue_root(self, extra_patch_project_roots=None):
+    """Returns path where a patch should be applied to based on "patch_project".
+
+    Maps Rietveld's "patch_project" to a path of directories relative to
+    api.gclient.c.solutions[0].name which describe where to place the patch.
+
+    Args:
+      extra_patch_project_roots: Dict mapping project names to relative roots.
+
+    Returns:
+      Relative path or empty string if patch_project is not set or path for a
+      given is unknown.
+    """
+    # Property 'patch_project' is set by Rietveld, 'project' is set by git-try
+    # when TRYSERVER_PROJECT is present in codereview.settings.
+    patch_project = (self.m.properties.get('patch_project') or
+                     self.m.properties.get('project'))
+
+    # Please avoid adding projects into this hard-coded list unless your project
+    # CLs are being run by multiple recipes. Instead pass patch_project_roots to
+    # ensure_checkout.
+    patch_project_roots = {
+      'angle/angle': ['third_party', 'angle'],
+      'blink': ['third_party', 'WebKit'],
+      'v8': ['v8'],
+      'luci-py': ['luci'],
+      'recipes-py': ['recipes-py'],
+    }
+
+    # Make sure to update common projects (above) with extra projects (and not
+    # vice versa, so that recipes can override default values if needed.
+    if extra_patch_project_roots:
+      patch_project_roots.update(extra_patch_project_roots)
+
+    path_parts = patch_project_roots.get(patch_project)
+    return self.m.path.join(*path_parts) if path_parts else ''