git-cl: Print git push stdout.

Tbr: tandrii@chromium.org
Bug: 881860
Change-Id: I17dd5c3b6e3fc6da126487b03ea4fc5aa06c2898
Reviewed-on: https://chromium-review.googlesource.com/c/1326561
Reviewed-by: Edward Lesmes <ehmaldonado@chromium.org>
Commit-Queue: Edward Lesmes <ehmaldonado@chromium.org>

git_cl.py

@@ -2958,7 +2958,7 @@ class _GerritChangelistImpl(_ChangelistCodereviewBase):
       before_push = time_time()
       push_stdout = gclient_utils.CheckCallAndFilter(
           ['git', 'push', self.GetRemoteUrl(), refspec],
-          print_stdout=False,
+          print_stdout=True,
           # Flush after every line: useful for seeing progress when running as
           # recipe.
           filter_fn=lambda _: sys.stdout.flush())