[android] Add an API to load customized font config for testing.

When running WebKit layout tests, we need to load some fonts from Linux to
match baselines of chromium linux. However, font config file is
hard-coded in Skia now. This change add an API to customize font config
in skia.

https://codereview.appspot.com/6296067/

git-svn-id: http://skia.googlecode.com/svn/trunk@4316 2bbb7eff-a529-9590-31e7-b0007b416f81
4 files changed