fixed typo

Former-commit-id: 42ad845f6cc310892c390964e81f2120659ff688

lib/hooks/content/content-hooks-frames-web.js

@@ -265,7 +265,7 @@
 			}
 			return new FontFace(...arguments);
 		};
-		window.FontFace.toString = function () { return "function FontFace() { [native code]"; };
+		window.FontFace.toString = function () { return "function FontFace() { [native code] }"; };
 	}
 
 	if (window.IntersectionObserver) {
@@ -306,7 +306,7 @@
 				observers.set(intersectionObserver, { callback, options });
 				return intersectionObserver;
 			};
-			window.IntersectionObserver.toString = function () { return "function IntersectionObserver() { [native code]"; };
+			window.IntersectionObserver.toString = function () { return "function IntersectionObserver() { [native code] }"; };
 		}
 	}
 

lib/hooks/content/content-hooks-web.js

@@ -39,6 +39,6 @@
 		}
 		pushState.call(history, state, title, url);
 	};
-	history.pushState.toString = function () { return "function pushState() { [native code]"; };
+	history.pushState.toString = function () { return "function pushState() { [native code] }"; };
 
 })();