GitLab

* Pull out logic in ShortcutHelper for parsing shortcut properties
  into the ShortcutInfo struct.  This will be used by AppBannerManager.

* Passes ShortcutInfo structs around instead of 4 different parameters
  when creating shortcuts.

BUG=453170

Review URL: https://codereview.chromium.org/899543003

Cr-Commit-Position: refs/heads/master@{#314415}