Bug 120585 [clean up] needs two invocations until all clean ups are performed
org.eclipse.jdt.ui.tests/ui/org/eclipse/jdt/ui/tests/quickfix/CleanUpTest.java
buf.append("package test1;\n");
		buf.append("public class E1 {\n");
		buf.append("    public void foo() {\n");
		buf.append("    }\n");
		buf.append("}\n");
		String expected1= buf.toString();
		
		buf= new StringBuffer();
		buf.append("package test1;\n");
		buf.append("public class E2 {\n");
		buf.append("}\n");
		String expected2= buf.toString();
		
		buf= new StringBuffer();
		buf.append("package test2;\n");
		buf.append("import test1.E2;\n");
		buf.append("public class E3 extends E2 {\n");
		buf.append("}\n");
		String expected3= buf.toString();
		int numberOfFixes= 3;
		int offset= 0;
		String[] previews= new String[numberOfFixes];
		for (int i= offset; i < numberOfFixes; i++) {
			IFix fix= cleanUp.createFix(units[i]);
			assertNotNull("There are problems but no fix", fix);
			TextChange change= fix.createChange();
			assertNotNull("Null change for an existing fix", change);
			previews[i - offset]= change.getPreviewContent(null);
		}
		assertEqualStringsIgnoreOrder(previews, new String[] { expected1, expected2, expected3});