Change mapRectScaleTranslate to pass args/ret by value

This reverts commit 6092b6e0e57be20d2e1ad079c0af133d2f67bfd3.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2138943002

Review-Url: https://codereview.chromium.org/2138943002
6 files changed