Avoid ASSERT_NOT_REACHED in blink::floatValueForLength.

BUG=477786

Review URL: https://codereview.chromium.org/1083083005

git-svn-id: svn://svn.chromium.org/blink/trunk@193937 bbb929c8-8fbe-4397-9dbb-9b2b20218538
1 file changed