Removing the mutation in the factories for getting dep repositories

appengine/findit/waterfall/extract_deps_info_pipeline.py

Index: appengine/findit/waterfall/extract_deps_info_pipeline.py
diff --git a/appengine/findit/waterfall/extract_deps_info_pipeline.py b/appengine/findit/waterfall/extract_deps_info_pipeline.py
index 6389265f1044db9ea8dca815b244c3d97732a91c..351a09fd74441eef64d7aba086b7df56a030ef90 100644
--- a/appengine/findit/waterfall/extract_deps_info_pipeline.py
+++ b/appengine/findit/waterfall/extract_deps_info_pipeline.py
@@ -43,11 +43,16 @@ def _GetOSPlatformName(master_name, builder_name):  # pragma: no cover
     return 'all'  # Default to all platform.
 
 
+def _CachedGitilesRepositoryFactory(repo_url): # pragma: no cover

[Sharu Jiang, 2016/12/28 23:05:12]

Ditto, we have this in 3 different places, how about move this to a module in
gae_libs/?

[wrengr, 2016/12/29 20:57:31]

Done.

+  return cached_gitiles_repository.CachedGitilesRepository(
+      HttpClientAppengine(), repo_url)
+
+
 def _GetDependencies(chromium_revision, os_platform):
   """Returns the dependencies used by the specified chromium revision."""
   deps = {}
-  dep_fetcher=chrome_dependency_fetcher.ChromeDependencyFetcher(
-      cached_gitiles_repository.CachedGitilesRepository(HttpClientAppengine()))
+  dep_fetcher = chrome_dependency_fetcher.ChromeDependencyFetcher(
+      _CachedGitilesRepositoryFactory)
   for path, dependency in dep_fetcher.GetDependency(
       chromium_revision, os_platform).iteritems():
     deps[path] = {
@@ -80,8 +85,8 @@ def _DetectDependencyRolls(change_logs, os_platform):
     }
   """
   deps_rolls = {}
-  dep_fetcher=chrome_dependency_fetcher.ChromeDependencyFetcher(
-      cached_gitiles_repository.CachedGitilesRepository(HttpClientAppengine()))
+  dep_fetcher = chrome_dependency_fetcher.ChromeDependencyFetcher(
+      _CachedGitilesRepositoryFactory)
   for revision, change_log in change_logs.iteritems():
     # Check DEPS roll only if the chromium DEPS file is changed by the CL.
     for touched_file in change_log['touched_files']: