A holdover from citra, the Horizon kernel on the switch has no
prominent kernel object that functions as a timer. At least not
to the degree of sophistication that this class provided.

As such, this can be removed entirely. This class also wasn't used at
all in any meaningful way within the core, so this was just code sitting
around doing nothing. This also allows removing a few things from the
main KernelCore class that allows it to use slightly less resources
overall (though very minor and not anything really noticeable).

With shader caches on the horizon, one requirement is to provide visible
feedback for the progress. The shader cache reportedly takes several
minutes to load for large caches that were invalidated, and as such we
should provide a loading screen with progress.

Adds a loading screen widget that will be shown until the first frame of
the game is swapped. This was chosen in case shader caches are not being
used, several games still take more than a few seconds to launch and
could benefit from a loading screen.

Allows removing the inclusion of the main input common header from the
UI config header.

'this' isn't actually used within the lambda, since what we need
from the class is already assigned within the capture section of
the lambda.

It's a common UI pattern to use an ellipsis to indicate an ongoing
action, rather than just specifying the word by itself.

This is a function that definitely doesn't always have a non-modifying
behavior across all implementations, so this should be made non-const.

This gets rid of the need to mark data members as mutable to work around
the fact mutating data members needs to occur.

Avoids the need to potentially reallocate the contained callbacks.

These currently aren't used by anything other than the QtWebBrowser
class itself, and can be made private.

Stored as signed seconds since epoch.

Pulse is considered a hack and nothing should be using it. We should completely remove it

The QPixmap API expects an unsigned int.