Update the manage button to the new style

Also fixes a bug where the overflow view would still leave space
for the manage button even though we don't show something there.

Bug: 183658858
Test: manual - open a bubble and observe the manage button, should
               be on a dark background with light text regardless
               of light / dark theme.
Change-Id: Ie3f67ccd26ad4d75a3ed21a3dee43e2f74d07022