Revert "Remove all safesync_url functionality from gclient"

recipe_modules/gclient/api.py

Index: recipe_modules/gclient/api.py
diff --git a/recipe_modules/gclient/api.py b/recipe_modules/gclient/api.py
index 64233fca439c258168d0d1dafdea37c0bb22cf23..595939ace6fb5cbfce780670026471dc0ccca148 100644
--- a/recipe_modules/gclient/api.py
+++ b/recipe_modules/gclient/api.py
@@ -133,6 +133,8 @@ class GclientApi(recipe_api.RecipeApi):
     revisions = []
     self.set_patch_project_revision(self.m.properties.get('patch_project'), cfg)
     for i, s in enumerate(cfg.solutions):
+      if s.safesync_url:  # prefer safesync_url in gclient mode
+        continue
       if i == 0 and s.revision is None:
         s.revision = RevisionFallbackChain()