Bug 131516 [Browser] NullPointerException in MozillaBrowser.openURL()
In MozillaBrowser.openURL() there is no check to see if the argument url2 is null before calling url2.toExternalForm(). So passing in null to this method results in a NullPointerException.
bundles/org.eclipse.ui.browser/src/org/eclipse/ui/internal/browser/browsers/MozillaBrowser.java
public boolean exitRequested = false;
		private String url;
		public BrowserThread(String urlName) {
			this.url = urlName;
		}
		/**
		 * @param browserCmd
		 * @return int 0 if success
		 */
		private int openBrowser(String browserCmd) {
			try {
				Process pr = Runtime.getRuntime().exec(browserCmd);
				StreamConsumer outputs = new StreamConsumer(pr.getInputStream());
				(outputs).start();
				StreamConsumer errors = new StreamConsumer(pr.getErrorStream());