Remove [LegacyTreatAsPartialInterface] from SVGFilterPrimitiveStandardAttributes

Easy one (just remove static member function wrappers),
lots of uses (some SVG doc links).
This finishes SVG 'implements' cleanup!
(Still have 7 other interfaces to fix.)

R=haraken
BUG=360435

Review URL: https://codereview.chromium.org/230523002

git-svn-id: svn://svn.chromium.org/blink/trunk@171139 bbb929c8-8fbe-4397-9dbb-9b2b20218538