Fix media permission grant dialog regression

The CL ag/17898785 introduced a regression, resulting in incorrect
dialog prompts for media permissions, which in turn led to incorrect
permissions being applied.

This fixes the regression.

Fixes: 232303866
Fixes: 231839805
Test: atest MediaPermissionTest MediaPermissionUpgradeTest
Test: manually as described in both bugs
Change-Id: I937b4b9f7987ed3a2f6619c41e3b458b0a63d0f1