Update release script with a --no-bugs option

Change-Id: I61b5d6b6f33670559218ee68ad22097e6166e2ae
diff --git a/tools/r8_release.py b/tools/r8_release.py
index 38feb27..867d312 100755
--- a/tools/r8_release.py
+++ b/tools/r8_release.py
@@ -893,6 +893,10 @@
                       default=[],
                       action='append',
                       help='List of bugs for release version')
+  result.add_argument('--no-bugs',
+                      default=False,
+                      action='store_true',
+                      help='Allow Studio release without specifying any bugs')
   result.add_argument('--studio',
                       metavar=('<path>'),
                       help='Release for studio by setting the path to a studio '
@@ -938,10 +942,15 @@
                       metavar=('<path>'),
                       help='Location for dry run output.')
   args = result.parse_args()
+  if (len(args.bug) > 0 and args.no_bugs):
+    print("Use of '--bug' and '--no-bugs' are mutually exclusive")
+    sys.exit(1)
+
   if (args.studio
       and args.version
       and not 'dev' in args.version
-      and args.bug == []):
+      and args.bug == []
+      and not args.no_bugs):
     print("When releasing a release version to Android Studio add the "
            + "list of bugs by using '--bug'")
     sys.exit(1)