LibDevTools was implicitly including generated IPC endpoints from
LibWebView. This is not a dependency declared in the CMakeLists.txt. So
updates to the IPC file might not have caused the endpoint header to be
regenerated by the time LibDevTools is compiled, resulting in a build
error.
This patch removes that implicit dependency entirely.
There is a lot needed all at once to actually inspect a tab's DOM tree.
It begins with requesting a "watcher" from a TabActor. It seems there
can be many types of watchers, but here we implement the "frame" watcher
only. The watcher creates an "inspector", which in turn creates a
"walker", which is the actor ultimately responsible for serializing and
inspecting the DOM tree.
In between all that, the DevTools client will send a handful of other
informational requests. If we do not reply to these, the client will not
move forward with the walker. For example, the CSSPropertiesActor will
be asked for a list of all known CSS properties.