Reconfigure blink to match previous configuration.
Reconfigure blink to match previous configuration.

This removes gclient_revert (which wasn't present in https://chromium.googlesource.com/chromium/tools/build/+/master/masters/master.chromium.webkit/master_gatekeeper_cfg.py). It also makes all steps optionally closing, meaning if they aren't present they don't close the tree. This obviates the need to specify the recipe steps separately, leading to a cleaner config file and less needless tree redness.

BUG=359314

Review URL: https://codereview.chromium.org/227123006

git-svn-id: 239fca9b83025a0b6f823aeeca02ba5be3d9fd76@262198 0039d316-1c4b-4281-b951-d872f2087c98

eunchong/build,eunchong/build,eunchong/build,eunchong/build