git: git-gui crashing

[mkae (Marko Käning)]

This happens reproducibly on Sierra 10.12.1:

$ git gui
2016-10-25 20:10:37.108 Wish[21174:142500] *** Terminating app due to uncaught exception 'CALayerInvalidGeometry', reason: 'CALayer position contains NaN: [0 nan]'
*** First throw call stack:
(
	0   CoreFoundation                      0x00007fffbdc3c48b __exceptionPreprocess + 171
	1   libobjc.A.dylib                     0x00007fffd239ecad objc_exception_throw + 48
	2   CoreFoundation                      0x00007fffbdcba96d +[NSException raise:format:] + 205
	3   QuartzCore                          0x00007fffc37e1520 _ZN2CA5Layer12set_positionERKNS_4Vec2IdEEb + 152
	4   QuartzCore                          0x00007fffc37e1695 -[CALayer setPosition:] + 44
	5   QuartzCore                          0x00007fffc37e1ceb -[CALayer setFrame:] + 644
	6   CoreUI                              0x00007fffc95a94ce _ZN20CUICoreThemeRenderer26MakeOrUpdateScrollBarLayerEPK13CUIDescriptoraPP7CALayer + 1284
	7   CoreUI                              0x00007fffc95a54c3 _ZN20CUICoreThemeRenderer19CreateOrUpdateLayerEPK13CUIDescriptorPP7CALayer + 1595
	8   CoreUI                              0x00007fffc952658d _ZN11CUIRenderer19CreateOrUpdateLayerEPK14__CFDictionaryPP7CALayer + 175
	9   CoreUI                              0x00007fffc9529241 CUICreateOrUpdateLayer + 221
	10  AppKit                              0x00007fffbc26821f -[NSCompositeAppearance _callCoreUIWithBlock:options:] + 226
	11  AppKit                              0x00007fffbb90e0b3 -[NSAppearance _createOrUpdateLayer:options:] + 76
	12  AppKit                              0x00007fffbbb8671f -[NSScrollerImp _animateToRolloverState] + 274
	13  AppKit                              0x00007fffbbb460f9 __49-[NSScrollerImp _installDelayedRolloverAnimation]_block_invoke + 673
	14  AppKit                              0x00007fffbba0c2c5 -[NSScrollerImp _doWork:] + 15
	15  Foundation                          0x00007fffbf61ac88 __NSFireDelayedPerform + 417
	16  CoreFoundation                      0x00007fffbdbbbd74 __CFRUNLOOP_IS_CALLING_OUT_TO_A_TIMER_CALLBACK_FUNCTION__ + 20
	17  CoreFoundation                      0x00007fffbdbbb9ff __CFRunLoopDoTimer + 1071
	18  CoreFoundation                      0x00007fffbdbbb55a __CFRunLoopDoTimers + 298
	19  CoreFoundation                      0x00007fffbdbb2f81 __CFRunLoopRun + 2065
	20  CoreFoundation                      0x00007fffbdbb2514 CFRunLoopRunSpecific + 420
	21  Tcl                                 0x000000010d22eb43 Tcl_WaitForEvent + 314
	22  Tcl                                 0x000000010d1fe5cd Tcl_DoOneEvent + 274
	23  Tk                                  0x000000010d06bf4f Tk_MainLoop + 33
	24  Tk                                  0x000000010d077a5b Tk_MainEx + 1566
	25  Wish                                0x000000010d04b55a Wish + 9562
	26  libdyld.dylib                       0x00007fffd2c7d255 start + 1
)
libc++abi.dylib: terminating with uncaught exception of type NSException
error: git-gui died of signal 6

but worked on Mavericks and El Capitan.

The only difference there is, that git gui starts on Sierra with the warning message:

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It briefly displays the gui's dialog before it crashes.