Drop obsolete --git-deps parameter to gclient.

BUG=406935
R=cmp@chromium.org,iannucci@chromium.org

Review URL: https://codereview.chromium.org/502863002

Cr-Commit-Position: refs/heads/master@{#291641}

tools/auto_bisect/bisect_utils.py

@@ -281,7 +281,7 @@ def RunGClientAndCreateConfig(opts, custom_deps=None, cwd=None):
     spec += GCLIENT_SPEC_ANDROID
 
   return_code = RunGClient(
-      ['config', '--spec=%s' % spec, '--git-deps'], cwd=cwd)
+      ['config', '--spec=%s' % spec], cwd=cwd)
   return return_code