Add toString() to Browser showing the underlying browser type

Override Browser.toString() to append the active browser backend (e.g.
"webkit", "edge", "ie", "safari") returned by getBrowserType(). This
makes it easy to see in the debugger or in logs which native browser
implementation a Browser instance is using, without having to drill
into the internal webBrowser field.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: vogella

bundles/org.eclipse.swt/Eclipse SWT Browser/common/org/eclipse/swt/browser/Browser.java

@@ -1276,4 +1276,11 @@ public void stop () {
 	checkWidget();
 	webBrowser.stop ();
 }
+
+@Override
+public String toString () {
+	String base = super.toString ();
+	if (webBrowser == null) return base;
+	return base + " [" + webBrowser.getBrowserType () + "]";
+}
 }