Fixes for WebContents associated interfaces support
These weren't caught in the original CL
) since that CL
intentionally didn't exercise everything.
I neglected to test the follow-up CL completely before
landing the first one, so I missed these bugs:
1. WebContentsBindingSet::Binding needs to be exported
2. The RouteProvider proxy in RPHI needs to reset on Init
3. RenderFrameImpl never implemented
*crawls into shame cube*
Landing these fixes separately from the follow-up CL
) to retain its
purpose as a minimal example of WebContents IPC conversion.