[SVGDom] Add clip-rule support

Currently we use 'fill-rule' when emitting clip paths.  This is wrong:
per spec [1], clip paths observe 'clip-rule', not 'fill-rule'.

[1] https://www.w3.org/TR/SVG/masking.html#ClipRuleProperty

Change-Id: Idf81de05e9601663c8dbc9856900ffa679daf4a5
Reviewed-on: https://skia-review.googlesource.com/57661
Reviewed-by: Robert Phillips <robertphillips@google.com>
Reviewed-by: Stephan Altmueller <stephana@google.com>
Commit-Queue: Florin Malita <fmalita@chromium.org>
11 files changed