Fix "Receiving Backlog" after destroying and rebuilding activity.

The problem was that every non-done init progress event was
re-setting the initDone boolean to false, causing it to think
the init was not complete when it actually was.  Additionally,
the updateInitProgress() call for "Receiving backlog" was
at the end of the code that processed BufferViewConfig events,
which became an inaccurate location after the hardcoded
bufferViewId was fixed.