Enable SVG in webkit

Some minor changes to enable SVG in the webkit library.  The details can be found here: https://review.source.android.com//#change,17258

Applying these changes and building with the flags ENABLE_SVG and ENABLE_SVG ANIMATION set to true will build webkit with support for SVG. 

The resulting libwebcore.so will be about 700KB larger, but the file size is a non-issue with modern devices.

Thanks for your consideration.