This patch replaces the bespoke rendering engine in Presenter with a
simple pipeline that turns presentations into single-page HTML files.
The HTML is then loaded into an OutOfProcessWebView.
This achieves a number of things, most importantly:
- Access to all the CSS features supported by LibWeb
- Sandboxed, multi-process rendering
The code could be simplified a lot further, but I wanted to get the new
architecture in place without changing anything about the file format.
Rip that bandaid off!
This does the following, in one big, awkward jump:
- Replace all uses of `set_main_widget<Foo>()` with the `try` version.
- Remove `set_main_widget<Foo>()`.
- Rename the `try` version to just be `set_main_widget` because it's now
the only one.
The majority of places that call `set_main_widget<Foo>()` are inside
constructors, so this unfortunately gives us a big batch of new
`release_value_but_fixme_should_propagate_errors()` calls.
We have a new, improved string type coming up in AK (OOM aware, no null
state), and while it's going to use UTF-8, the name UTF8String is a
mouthful - so let's free up the String name by renaming the existing
class.
Making the old one have an annoying name will hopefully also help with
quick adoption :^)
This version can already:
- load all of the defined file format except for the image type and the
frame-specific stuff
- navigate frames and slides (though frames are mostly stubbed out)
- display text with various common settings
- displays text with various fitting and scaling methods
- scale and position objects correctly no matter the window size
