Fix Bug 879 Regression (2/2) - NewtCanvasAWT.FocusAction must take focus when in offscreen-mode (OSX/CALayer)

NewtCanvasAWT.FocusAction must take focus when in offscreen-mode (OSX/CALayer)
since the NEWT window _is_ offscreen (no input events) and AWT events are translated to NEWT.

Regression of commit 0be87f241c0f0b2f5881d9a602ce12378b8e453d