Split JS::ErrorData out of JS::Error so that it can be used both
by JS::Error and WebIDL::DOMException. This adds support for
Error.isError to DOMException, also letting us report DOMException
stack information to the console.
Previously, console messages were sent using an index-based system where
DevTools would be notified of new message indices and then request them
in batches. This created synchronization issues during page navigation
when the WebContent process resets while DevTools still has stale index
state.
This changes to a push-based model where console messages are sent
immediately as resources when they are logged, matching how Firefox
DevTools handles console messages. Each message is pushed through IPC
and forwarded to DevTools as a "console-message" or "error-message"
resource.
This eliminates the need for index tracking in FrameActor and simplifies
the entire console message pipeline from WebContent through to DevTools.
The idea originally was that the WebContentConsoleClient would perform
some amount of console handling that both InspectorConsoleClient and
DevToolsConsoleClient needed. But in implementing the DevTools console,
it's become clear that these implementations will not overlap at all. So
this patch moves the existing Inspector functionality away from
WebContentConsoleClient.
Our existing WebContentConsoleClient is very specific to our home-grown
Inspector. It renders console output to an HTML string. For DevTools, we
will not want this behavior; we will want to send representations of raw
JS values.
This patch makes WebContentConsoleClient a base class to handle console
input from the user, either from the Inspector or from DevTools. It then
moves the HTML rendering needed for the Inspector to a new class,
InspectorConsoleClient. And we add a DevToolsConsoleClient (currently
just stubbed) to handle needs specific to DevTools.
We choose at runtime which console client to install, based on the
--devtools command line flag.
