Provides a nicer experience on pages with large trees so that the window
isn't just a large blank screen while it is loading. Instead, send the
trees to the Inspector WebView once they have arrived and have been
transformed to HTML.
We Base64 encode the HTML to avoid needing to deal with all kinds of
nested quotes that may appear in the HTML. We could instead send the
JSON to the WebView, but generating the HTML in C++ feels a bit easier
for now.
This is modeled after a similar implementation for the JS console.
This client takes over an inspector WebView (created by the chrome) to
create the inspector application. Currently, this application includes
the DOM tree and accessibility tree as a first pass. It can later be
extended to included the style tables, the JS console itself, etc.
