bisect-kit: workaround issue of repo mirror chromeos' manifest-internal

BUG=chromium:893441
TEST="bisect_cros_repo.py init" with clean repo mirror
     (without other manifest-internal workaround)

Change-Id: Id450710ddeab3bb79428c2e4975739e9673ba8e5
Reviewed-on: https://chromium-review.googlesource.com/1278515
Commit-Ready: Kuang-che Wu <kcwu@chromium.org>
Tested-by: Kuang-che Wu <kcwu@chromium.org>
Reviewed-by: Chung-yih Wang <cywang@chromium.org>
diff --git a/bisect_kit/repo_util.py b/bisect_kit/repo_util.py
index 121e148..3ae07af 100644
--- a/bisect_kit/repo_util.py
+++ b/bisect_kit/repo_util.py
@@ -294,6 +294,12 @@
 
   def cached_git_root(self, repo_url):
     cache_path = self._url_to_cache_dir(repo_url)
+
+    # The location of chromeos manifest-internal repo mirror is irregular
+    # (http://crbug.com/895957). This is a workaround.
+    if cache_path == 'chromeos/manifest-internal.git':
+      cache_path = 'manifest-internal.git'
+
     return os.path.join(self.mirror_dir, cache_path)
 
   def _load_project_list(self, project_root):