Add a Java FindAddress implentation.

This stops calling findAddress (possibly indirectly via Linkify) from
loading webview native code, resulting in a performance and memory
improvement for those apps that call WebView#findAddress but do not
otherwise use WebView.

Bug: 22362008
Test: Existing WebView CTS test.
Change-Id: I5fcab725ceaf0d6a00e931d3b6cd2f3799d68391