Bug 40785 [plan item] Overview ruler improvements
- navigation from ruler to editor - hovering over header area shows number of errors/warning (header annotations in general)
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/javaeditor/filebuffers/CompilationUnitDocumentProvider2.java
}
			
			/*
			 * @see IProblemRequestor#beginReporting()
			 */
			public void beginReporting() {
				if (fCompilationUnit != null && fCompilationUnit.getJavaProject().isOnClasspath(fCompilationUnit))
					fCollectedProblems= new ArrayList();
				else
					fCollectedProblems= null;
			}
			
			/*
			 * @see IProblemRequestor#acceptProblem(IProblem)
			 */
			public void acceptProblem(IProblem problem) {
				if (isActive())
					fCollectedProblems.add(problem);
			}
			/*
			 * @see IProblemRequestor#endReporting()
			 */
			public void endReporting() {
				if (!isActive())
					return;
					
				if (fProgressMonitor != null && fProgressMonitor.isCanceled())
					return;