This implements an autocomplete engine inside LibWebView, to replace the
engine currently used by Qt. Whereas Qt uses the Qt Network framework to
perform autocomplete requests, LibWebView uses RequestServer. This moves
downloading this untrusted data out of the browser process.
This patch only implements the persisted settings and their UI. It does
not integrate this engine into the browser UI.
When we build internal pages (e.g. about:settings), there is currently
quite a lot of boilerplate needed to communicate between the browser and
the page. This includes creating IDL for the page and the IPC for every
message sent between the processes.
These internal pages are also special in that they have privileged
access to and control over the browser process.
The framework introduced here serves to ease the setup of new internal
pages and to reduce the access that WebContent processes have to the
browser process. WebUI pages can send requests to the browser process
via a `ladybird.sendMessage` API. Responses from the browser are passed
through a WebUIMessage event. So, for example, an internal page may:
ladybird.sendMessage("getDataFor", { id: 123 });
document.addEventListener("WebUIMessage", event => {
if (event.name === "gotData") {
console.assert(event.data.id === 123);
}
});
To handle these messages, we set up a new IPC connection between the
browser and WebContent processes. This connection is torn down when
the user navigates away from the internal page.
This adds a WebView::Settings class to own persistent browser settings.
In this first pass, it now owns the new tab page URL and search engine
settings.
For simplicitly, we currently use a JSON format for these settings. They
are stored alongside the cookie database. As of this commit, the saved
JSON will have the form:
{
"newTabPageURL": "about:blank",
"searchEngine": {
"name": "Google"
}
}
(The search engine is an object to allow room for a future patch to
implement custom search engine URLs.)
For Qt, this replaces the management of these particular settings in the
Qt settings UI. We will have an internal browser page to control these
settings instead. In the future, we will want to port all settings to
this new class. We will also want to allow UI-specific settings (such as
whether the hamburger menu is displayed in Qt).
When we inspect a DOM node, we currently serialize many properties for
that node, including its layout, computed style, used fonts, etc. Now
that we aren't piggy-backing on the Inspector interface, we can instead
only serialize the specific information required by DevTools.
Since cross-site navigation is a pretty frequent task, creating a spare
process is commonplace in other browsers to reduce the overhead of
directing the target site to a new process.
We store this process on the WebView application. If it is unavailable,
we queue a task to create it later.
