Add UseCounters for the use of xml:lang in SVG

Apart from the reflect SVGElement.xmllang, this is the only place in
Blink where xml:lang has an observable effect. Count usage to help
determine what, if anything, should be done with xml:lang. Discussed in
https://code.google.com/p/chromium/issues/detail?id=341854#c7

Note that else-branch where anything other than "preserve" is handled
does not seem per spec: http://www.w3.org/TR/xml11/#sec-white-space

BUG=341854

Review URL: https://codereview.chromium.org/890863003

git-svn-id: svn://svn.chromium.org/blink/trunk@189263 bbb929c8-8fbe-4397-9dbb-9b2b20218538
2 files changed
tree: 10826fc0aecbaa10d9911bdc046f58b173714851
  1. third_party/