Check if input element is a range control before painting slider ticks

We weren't checking if the input element is a range control inside paintSliderTicks and so we were hitting an assert.

TEST=Automated. Added slider-appearance-with-ticks-crash.html.
BUG=350905

Review URL: https://codereview.chromium.org/194273004

git-svn-id: svn://svn.chromium.org/blink/trunk@169936 bbb929c8-8fbe-4397-9dbb-9b2b20218538