Remove unused runtime setting shouldpaintnativecontrols
Remove unused runtime setting shouldpaintnativecontrols

This setting existed in WebKit but Chromium never changed it from its default value. We're removing all such unchanging settings in Blink, along with their associated code.

R=abarth@chromium.org
BUG=226711

Review URL: https://codereview.chromium.org/13919002

git-svn-id: bf5cd6ccde378db821296732a091cfbcf5285fbd@148048 bbb929c8-8fbe-4397-9dbb-9b2b20218538

primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs