When cherry pick was successful, open new created change. To implement
the URL computation, existing method _computeChangePath() was moved
from change view to REST client behaviour to reuse from change action
element.
TODOs:
- implement branch name suggestion oracle
- improve error handling when branch or message is missing (alert)
- improve error handling when conflict occurs (409)
- improve error handling when branch doesn't exist (400)
Test Plan:
1. Open a change
2. Click Cherry Pick button
3. Type destination branch and click confirm button
4. Confirm, that the change cherry-picked and new change is opened
Bug: Issue 3906
Change-Id: I587f541dbc3338dc138f306c400f5f8857fd16a3
e877140440