To allow implementing the DOM class hierarchy in JS bindings, this
patch adds an inherits() function that can be used to ask an Object
if it inherits from a specific C++ class (by name).
The necessary overrides are baked into each Object subclass by the
new JS_OBJECT macro, which works similarly to C_OBJECT in LibCore.
Thanks to @Dexesttp for suggesting this approach. :^)
More work towards supporting multiple global objects. Native C++ code
now get a GlobalObject& and don't have to ask the Interpreter for it.
I've added macros for declaring and defining native callbacks since
this was pretty tedious and this makes it easier next time we want to
change any of these signatures.
Introduce support for the both of these Math methods.
Math.trunc is implemented in terms of Math.ceil or Math.floor
based on the input value. Added tests as well.
Instead of implementing every native function as a lambda function,
use static member functions instead.
This makes it easier to navigate the code + backtraces look nicer. :^)
