Add a --hash option to run_on_app.py

Change-Id: I42beef4c189e33e2d9f4d436bbc06db3cabf8079
diff --git a/tools/utils.py b/tools/utils.py
index 5396c0a..bed28d8 100644
--- a/tools/utils.py
+++ b/tools/utils.py
@@ -316,9 +316,9 @@
   PrintCmd(cmd)
   return subprocess.call(cmd) == 0
 
-def download_file_from_cloud_storage(source, destination):
+def download_file_from_cloud_storage(source, destination, quiet=False):
   cmd = ['gsutil.py', 'cp', source, destination]
-  PrintCmd(cmd)
+  PrintCmd(cmd, quiet=quiet)
   subprocess.check_call(cmd)
 
 def create_archive(name, sources=None):