Fixed: windows that were autoresized and not constrainable would obey the global CPWindowConstrainToScreen flag.

Previously, if a window had an autoresizingMask and was marked as not being constrained (for example _CPMenuBarWindow), and the CPWindowConstrainToScreen was set to NO, resizing the platform window would not autoresize the window.

This commit ensures that windows that autoresize but don't care about constraining will resize with the platform window no matter what.

Fixes #1981.
Fixed: background-color was rendering subviews invisible.
Fixed: text fields in full platform windows could not be selected.
Fixed: Compiler now generates correct empty statement after 'if (a);'

Earlier the compiler generated the 'if' without the last ';' when a empty statement is used, with sometimes devastating result. The same if an empty statement was after the 'else'.

I have also added a test case for some different empty statement senarios.
Merge pull request #1984 from mrcarlberg/if-empty-statement

Fixed: Compiler now generates correct empty statement after 'if (a);'