SystemUI: use path specification for rounded corners

Some devices do not have perfectly circular corner and using the existing method looks weird.
This parses a path string and uses that for the corner paths. When "config_rounded_mask" is not overridden, a circular corner path will be used.

Test: manual. The corner path drawn was correct on screen and looked great.

Change-Id: I593f328663128621aba52712525b59f1e2d193ac
1 file changed