Set default value of gridName to current grid name in GridOptionsProvider

With grid preview, a grid name is passed in when requesting preview under different grid setting. With wallpaper preview, no such grid name will be passed in, and it should be set to the current.

Bug: 145242344
Test: N/A
Change-Id: I282cb5341b7f3756d41c4abd8d97f986abaa6d27
2 files changed