GitLab

Update the following icons used in the Ash material
design system menu:

* Caps lock
* Auto rotation
* Auto rotation locked
* System update available

Furthermore, color the system update icon in the
system tray and system menu in response to the
severity of the update. The colors chosen for
each severity level match those used by the
system update icon in material design top chrome.

BUG=625690
TEST=manual

Review-Url: https://codereview.chromium.org/2252823002
Cr-Commit-Position: refs/heads/master@{#412609}