Bug 6718 Error ticks on non-Java resources
This is a VAME request. They would like to show error ticks on manifest files.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/viewsupport/ProblemMarkerManager.java
private PkgFragmentRootErrorVisitor fPkgFragmentRootErrorVisitor;
		private HashSet fChangedElements; 
		
		public ProjectErrorVisitor(HashSet changedElements) {
			fPkgFragmentRootErrorVisitor= new PkgFragmentRootErrorVisitor();
			fChangedElements= changedElements;
		}
			
		public boolean visit(IResourceDelta delta) throws CoreException {
			IResource res= delta.getResource();
			if (res instanceof IProject && delta.getKind() == IResourceDelta.CHANGED) {
				try {
					IJavaProject jProject= getJavaProject((IProject)res);
					if (jProject != null) {
						checkInvalidate(delta, res.getFullPath());
						
						IClasspathEntry[] cps= jProject.getRawClasspath();
						for (int i= 0; i < cps.length; i++) {
							if (cps[i].getEntryKind() == IClasspathEntry.CPE_SOURCE) {
								fPkgFragmentRootErrorVisitor.init(cps[i].getPath());
								delta.accept(fPkgFragmentRootErrorVisitor);
							}
						}
					}
				} catch (CoreException e) {
					JavaPlugin.log(e.getStatus());
				}
				return false;
			}
			return true;