fix(sort): arrow indicator not visible in high contrast mode (#12159)
fix(sort): arrow indicator not visible in high contrast mode (#12159)

Fixes the sorting header indicator not being visible in high contrast mode.
jelbourn/material2,mmalerba/material2,josephperrott/material2,DevVersion/material2,crisbeto/material2,Jefiozie/material2,andrewseguin/material2,amcdnl/material2,amcdnl/material2,josephperrott/material2,angular/components,DevVersion/material2,mmalerba/material2,andrewseguin/material2,andrewseguin/material2,DevVersion/material2,crisbeto/material2,mmalerba/material2,jelbourn/material2,DevVersion/material2,angular/components,josephperrott/material2,jelbourn/material2,josephperrott/material2,crisbeto/material2,Jefiozie/material2,amcdnl/material2,andrewseguin/material2,josephperrott/material2,Jefiozie/material2,andrewseguin/material2,jelbourn/material2,angular/components,Jefiozie/material2,angular/components,mmalerba/material2,crisbeto/material2,DevVersion/material2,Jefiozie/material2,jelbourn/material2,amcdnl/material2,amcdnl/material2,mmalerba/material2