Web Animations: Always use svg prefix when animating SVG attributes

Some SVG attribute names collide with CSS property names, and the
'offset' attribute collides with the use of 'offset' in Web Animations.

We avoid conflicts by using 'svgOffset', etc. when animating SVG
attributes using Web Animations.

BUG=416735

Review URL: https://codereview.chromium.org/1151573017

git-svn-id: svn://svn.chromium.org/blink/trunk@196744 bbb929c8-8fbe-4397-9dbb-9b2b20218538
2 files changed