The following issues are all part of a UI overhaul:

1 - 557786 - Mobile dialogues for switching sync accounts need improvement on Clank
2 - 557784 - Improve and Simplify Mobile Account Management UX on Clank
3 - 557781 - Unify and Improve the Sign-In and Sync Confirmation Screens on Clank

Issues 1 & 2 had landed before branch point, however  issue 3  caused a downstream test to fail so was reverted (http://crbug.com/590238) . These changes need to be made together. This means that either:

-  Issue 3  needs to be fixed and merged in.
- Issues 1 & 2 need to be taken out.

In addition, a bug fix for  issue 2  was merged after the branch point, so would be included in the merge.