IllegalArgumentException when changing zoom while editor is open

[ptziegler]

This only happens sporadically, but usually when switching from 150% to 175% monitor zoom.

java.lang.IllegalArgumentException: Argument not valid
	at org.eclipse.swt.SWT.error(SWT.java:4931)
	at org.eclipse.swt.SWT.error(SWT.java:4865)
	at org.eclipse.swt.SWT.error(SWT.java:4836)
	at org.eclipse.swt.graphics.GC.drawBitmap(GC.java:1509)
	at org.eclipse.swt.graphics.GC.drawImage(GC.java:1351)
	at org.eclipse.swt.graphics.GC.drawImage(GC.java:1265)
	at org.eclipse.swt.graphics.GC$DrawScalingImageToImageOperation.apply(GC.java:1183)
	at org.eclipse.swt.graphics.GC.storeAndApplyOperationForExistingHandle(GC.java:6047)
	at org.eclipse.swt.graphics.GC.drawImage(GC.java:1111)
	at org.eclipse.draw2d.BufferedGraphicsSource.flushGraphics(BufferedGraphicsSource.java:69)
	at org.eclipse.draw2d.DeferredUpdateManager.releaseGraphics(DeferredUpdateManager.java:264)
	at org.eclipse.draw2d.DeferredUpdateManager.repairDamage(DeferredUpdateManager.java:302)
	at org.eclipse.draw2d.DeferredUpdateManager.performUpdate(DeferredUpdateManager.java:180)
	at org.eclipse.draw2d.LightweightSystem.controlResized(LightweightSystem.java:124)
	at org.eclipse.draw2d.LightweightSystem$1.controlResized(LightweightSystem.java:107)
	at org.eclipse.swt.widgets.TypedListener.handleEvent(TypedListener.java:277)