Add generic action support in chrome.automation

- ARC++ actions
- web actions
- new apis to retrieve (AutomationNode.prototype.standardActions), trigger (AutomationNode.prototype.performAction)
- add PRESUBMIT to ensure actions keeps in sync
- add internal action type; public action type

TBR=dcheng@chromium.org

Bug: 830035
Cq-Include-Trybots: master.tryserver.chromium.linux:closure_compilation
Change-Id: I37ef59bd2dc977278595e3902d52aea7662308d0
Reviewed-on: https://chromium-review.googlesource.com/996795
Reviewed-by: David Tseng <dtseng@chromium.org>
Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Reviewed-by: Devlin <rdevlin.cronin@chromium.org>
Reviewed-by: Jorge Lucangeli Obes <jorgelo@chromium.org>
Reviewed-by: Dominic Mazzoni <dmazzoni@chromium.org>
Commit-Queue: David Tseng <dtseng@chromium.org>
Cr-Commit-Position: refs/heads/master@{#549324}
11 files changed