Repo should not fetch tags for shallow projects

Fetching all tags for a shallow git results in an
inconstent git and forces git to fetch more than
the depth specified.

This change teaches repo not to fetch any tags in a
repository initialised with the depth option.

Change-Id: I557ead9f88fa0d6a19b1cb55b23bba1100fcb8f2
Signed-off-by: Patrik Ryd <patrik.ryd@stericsson.com>

project.py

@@ -1661,7 +1661,9 @@ class Project(object):
 
     if not current_branch_only:
       # Fetch whole repo
-      if no_tags:
+      # If using depth then we should not get all the tags since they may
+      # be outside of the depth.
+      if no_tags or depth:
         cmd.append('--no-tags')
       else:
         cmd.append('--tags')