Force theme icons to stay on one row and adjust size to fit

Screenshots are from Pixel 5 at default icon size:
Before: http://screen/6ZFSVMqoNoDfGeQ
After: http://screen/B7453xAXSLa4kJf

Fixes: 250889939
Test: manually checked at different icon sizes on different devices
Change-Id: I1c66cd60bb16027851fe22eba8f46b457e0fe341