SVGLength: Avoid reading out-of-bounds when parsing incorrect 'rem' unit

The read/check of the third char ('m') could end up reading outside the
buffer if unlucky.

BUG=368598, 470449

Review URL: https://codereview.chromium.org/1069213003

git-svn-id: svn://svn.chromium.org/blink/trunk@193523 bbb929c8-8fbe-4397-9dbb-9b2b20218538
3 files changed
tree: ed8c0bd43505a56c2f627d54dea43664d99d66e3
  1. third_party/