GLJPanel Skip Vertical Flip Performance Tweak .. (Bug 904)

Bug 904: GLJPanel: Allow user to skip isGLOriented() based vertical flip of offscreen backend

+++

https://jogamp.org/bugzilla/show_bug.cgi?id=904
https://jogamp.org/bugzilla/attachment.cgi?id=541&action=edit

Windows7 - TestPerf001GLJPanelInit02AWT

GLJPanel-NOP__-AutoFlip:   total-i   633/t  25.32/1
GLJPanel-NOP__-ManualFlip: total-i   329/t  13.16/1

GLJPanel-Gears-AutoFlip:   total-i   996/t  39.84/1
GLJPanel-Gears-ManualFlip: total-i   777/t  31.08/1

+++

The test also shows how the vertical flip is performed in GearsES2
depending on the GLJPanel's drawable.isGLOriented().

Skipping vertical flipping in GLJPanel and performing it 'manually'
also takes out GL state known complications ..

However, it's optional.

~Sven