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.
The Inspector will have a split view, where the top view is that of the
exisiting DOM and accessibility trees, and the bottom view is that of
the currently inspected node's style properties. This patch generalizes
some of the generated code to support having these 2 views.
When scrolling to the inspected element, if we scroll to its exact
position, it would often be placed behind the fixed header at the top of
the WebView. This patch gives the scroll a bit of an offset to scroll
comfortably beneath the header.
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.