fix($location): parse xlink:href for SVGAElements

Before this fix, the xlink:href property of an SVG <a> element could not be parsed
on click, as the property is an SVGAnimatedString rather than a DOMString.

This patch parses the xlink:href's animVal into a DOMString in order to prevent
an `Object #<SVGAnimatedString> has no method 'indexOf'` exception from being thrown,
and also to update the location if necessary as expected.

Closes angular#5472
Closes angular#5198
Closes angular#5199
Closes angular#4098
Closes angular#1420

src/ng/location.js

@@ -629,6 +629,13 @@ function $LocationProvider(){
       }
 
       var absHref = elm.prop('href');
+
+      if (isObject(absHref) && absHref.toString() === '[object SVGAnimatedString]') {
+        // SVGAnimatedString.animVal should be identical to SVGAnimatedString.baseVal, unless during
+        // an animation.
+        absHref = urlResolve(absHref.animVal).href;
+      }
+
       var rewrittenUrl = $location.$$rewrite(absHref);
 
       if (absHref && !elm.attr('target') && rewrittenUrl && !event.isDefaultPrevented()) {

test/ng/locationSpec.js

@@ -1229,6 +1229,31 @@ describe('$location', function() {
       });
       browserTrigger(button, 'click');
     }));
+
+
+    it('should not throw when clicking an SVGAElement link', function() {
+      var base;
+      module(function($locationProvider) {
+        return function($browser) {
+          window.location.hash = '!someHash';
+          $browser.url(base = window.location.href);
+          base = base.split('#')[0];
+          $locationProvider.hashPrefix('!');
+        }
+      });
+      inject(function($rootScope, $compile, $browser, $rootElement, $document, $location) {
+        // we need to do this otherwise we can't simulate events
+        $document.find('body').append($rootElement);
+        var template = '<svg><g><a xlink:href="#!/view1"><circle r="50"></circle></a></g></svg>';
+        var element = $compile(template)($rootScope);
+
+        $rootElement.append(element);
+        var av1 = $rootElement.find('a').eq(0);
+        expect(function() {
+          browserTrigger(av1, 'click');
+        }).not.toThrow();
+      });
+    });
   });