Fix ~,! typo when clearing kRenderTarget flag

TBR=brucedawson@chromium.org,robertphillips@google.com
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1727413004

Review URL: https://codereview.chromium.org/1727413004 .
1 file changed