Update documentation for TranslateUtils::getIcon

Also readd the warning removed in Change-Id:
I24fb73e31ab9433bb6046014e5e6937910a8f8e4 with an updated
description.

Change-Id: I654ba943be0effd3d0568e1eca11115d3355f6ae
Merge "Update documentation for TranslateUtils::getIcon"