Add dummy awakeFromNib dummy method

[gcasa]

This adds a dummy method for NSView so that subclasses can call awakeFromNib. I have run into production code which does this and does not fail on macOS. I also have a test which I will add to git and reference here.

[gcasa]

Here is the test... https://github.com/gcasa/NSView_subclass_awakeFromNib_test

[fredkiefer]

This new method will result in a lot of useless calls but if Apple has it, we will need it too.

[gcasa]

@fredkiefer One additional suggestion I have on this... even though it is merged.

You lament that we are "making a lot of useless calls" yet it appears to me that in order to avoid making said useless calls we are invoking "respondsToSelector" in an if and THEN making the call instead of just assuming the method is always there, so, for the calls that don't have the method we are doing an "if" AND a respondsToSelector call anyway and for those that do have it we are doing both of those AND the call anyway.

I am wondering if it is more or less expensive to simply assume its presence rather than check for it, but that's a discussion for another time.

[fredkiefer]

Sounds like a valid solution to me. In that case we should move this method to NSObject.

[gcasa]

I would guess/bet that this method is implemented on NSObject via a category in AppKit. I am going to do some research today to see if that's the case.