Revert "Update dialog background color for dark theme"

This reverts commit 3032628269b1010e05e0c7f63d07d02c3230a818.

Reason for revert: This will also change the background color of other components within dialog.

Bug: 132753127
Bug: 132623454
Test: visual
Change-Id: I59d4731e84e8d516a01780c4cce70b2d86208098
4 files changed