highlighting: syntax errors can make whole file lose highlighting

for example entering \" in a string can do that. all highlighting disappears and the cursor goes to the beginning of the file

The reason is probably that the partition scanner fails and throws an exception, but it may be from somewhere else too

Caused by: java.lang.IllegalArgumentException: Argument not valid
        at org.eclipse.swt.SWT.error(SWT.java:4263)
        at org.eclipse.swt.SWT.error(SWT.java:4197)
        at org.eclipse.swt.SWT.error(SWT.java:4168)
        at org.eclipse.swt.custom.StyledText.setStyleRanges(StyledText.java:9680)
        at org.eclipse.swt.custom.StyledText.replaceStyleRanges(StyledText.java:7713)