fix($browser): use location.hash if only the hash has changed

Closes #9635

Author: petebacondarwin

src/ng/browser.js

@@ -1,6 +1,11 @@
 'use strict';
 /* global stripHash: true */
 
+function getHash(url) {
+  var index = url.indexOf('#');
+  return index === -1 ? '' : url.substr(index + 1);
+}
+
 /**
  * ! This is a private undocumented service !
  *
@@ -191,8 +196,10 @@ function Browser(window, document, $log, $sniffer) {
         }
         if (replace) {
           location.replace(url);
-        } else {
+        } else if (!sameBase) {
           location.href = url;
+        } else {
+          location.hash = getHash(url);
         }
       }
       return self;

test/ng/browserSpecs.js

@@ -1,5 +1,7 @@
 'use strict';
 
+/* global getHash:true, stripHash:true */
+
 var historyEntriesLength;
 var sniffer = {};
 
@@ -51,6 +53,12 @@ function MockWindow(options) {
       mockWindow.history.state = null;
       historyEntriesLength++;
     },
+    get hash() {
+      return getHash(locationHref);
+    },
+    set hash(value) {
+      locationHref = stripHash(locationHref) + '#' + value;
+    },
     replace: function(url) {
       locationHref = url;
       mockWindow.history.state = null;