Bug 49182 What should canceling setRawClasspath do ?
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/viewsupport/GoToBackProgressMonitorDialog.java
protected void finishedRun() {
	decrementNestingDepth();
	close();
}
/**
 * Sets whether the progress dialog is cancelable or not.
 *
 * @param cancelable <code>true</code> if the end user can cancel
 *   this progress dialog, and <code>false</code> if it cannot be canceled
 */
public void setCancelable(boolean cancelable) {
	if (cancel == null)
		enableCancelButton = cancelable;
	else
		asyncSetOperationCancelButtonEnabled(cancelable);
}
/**
 * Helper to enable/disable Cancel button for this dialog.
 *
 * @param b <code>true</code> to enable the cancel button,
 *   and <code>false</code> to disable it
 * @since 3.0
 */
protected void setOperationCancelButtonEnabled(boolean b) {
	operationCancelableState = b;
	cancel.setEnabled(b);
}
/*
 * @see org.eclipse.jface.dialogs.IconAndMessageDialog#getImage()
 */