Bug 52064 Content assist in "New Class" Dialog shows interfaces
Content Assist is available for the superclass in M7. However it also lists interfaces. If an interface is selected, the generated class "extends" it instead of "implementing" it.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/ui/wizards/NewTypeWizardPage.java
* 
	 * @return the text of the package input field
	 */
	public String getPackageText() {
		return fPackageDialogField.getText();
	}
	/**
	 * Returns the text of the enclosing type input field.
	 * 
	 * @return the text of the enclosing type input field
	 */	
	public String getEnclosingTypeText() {
		return fEnclosingTypeDialogField.getText();
	}	
	
	
	/**
	 * Returns the package fragment corresponding to the current input.
	 * 
	 * @return a package fragment or <code>null</code> if the input 
	 * could not be resolved.
	 */
	public IPackageFragment getPackageFragment() {
		if (!isEnclosingTypeSelected()) {
			return fCurrPackage;
		} else {
			if (fCurrEnclosingType != null) {
				return fCurrEnclosingType.getPackageFragment();
			}
		}