Bug 127655 [api] Must have a way to query quick assist context from source viewer
I20060214-0010 [api] Must have a way to query quick assist context from text viewer. In addition, quick assistant install must specify that besides ITextViewer also ITextViewerExtension7 must be present in order to get the invocation context. ==> assertion failure if this is not met.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/text/correction/JavaCorrectionProcessor.java
private final IInvocationContext fContext;
		private boolean fHasAssists;
		public SafeHasAssist(IInvocationContext context) {
			fContext= context;
			fHasAssists= false;
		}
		public boolean hasAssists() {
			return fHasAssists;
		}
		public void safeRun(ContributedProcessorDescriptor desc) throws Exception {
			IQuickAssistProcessor processor= (IQuickAssistProcessor) desc.getProcessor(fContext.getCompilationUnit());
			if (processor != null && processor.hasAssists(fContext)) {
				fHasAssists= true;
			}
		}
	}
	private static class SafeHasCorrections extends SafeCorrectionProcessorAccess {
		private final ICompilationUnit fCu;
		private final int fProblemId;
		private boolean fHasCorrections;