Revert "Restore shadowed text actor appearance to 5.6 quality."
Revert "Restore shadowed text actor appearance to 5.6 quality."

This reverts commit 35944bf09ccba7f42eb014678033395405feb9aA9.
Dashboards found a divide by zero in the alpha computation.

Change-Id: I1dd36aad689cd138cc3b912b7711ae4426d57b8f

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