Disable painting in a few more places

When GraphicsContext is given a NULL canvas, it should disable painting.
This patch amends a few operations where this check wasn't done. Most
notably, we no longer record display lists when painting is disabled.

BUG=357572

Review URL: https://codereview.chromium.org/216553003

git-svn-id: svn://svn.chromium.org/blink/trunk@170332 bbb929c8-8fbe-4397-9dbb-9b2b20218538