Allow EmbedRoot to be called multiple times.

mojo/services/view_manager/view_manager_unittest.cc

Index: mojo/services/view_manager/view_manager_unittest.cc
diff --git a/mojo/services/view_manager/view_manager_unittest.cc b/mojo/services/view_manager/view_manager_unittest.cc
index 73153737e56b037d7e0447f7a4f0039bbab139c5..259079648a04cd2fecdf9a1febf9995da4a6539d 100644
--- a/mojo/services/view_manager/view_manager_unittest.cc
+++ b/mojo/services/view_manager/view_manager_unittest.cc
@@ -318,7 +318,7 @@ class TestViewManagerClientConnection
     connection_.set_view_manager(client());
   }
 
-  // ViewMangerClient:
+  // ViewManagerClient:
   virtual void OnViewManagerConnectionEstablished(
       ConnectionSpecificId connection_id,
       const String& creator_url,
@@ -363,6 +363,9 @@ class TestViewManagerClientConnection
   }
   virtual void OnFocusChanged(Id gained_focus_id,
                               Id lost_focus_id) OVERRIDE {}
+  virtual void EmbedRoot(const String& url) OVERRIDE {
+    tracker_.OnEmbedRoot(url);
+  }
   virtual void DispatchOnViewInputEvent(Id view_id,
                                         mojo::EventPtr event) OVERRIDE {
   }
@@ -517,6 +520,12 @@ class ViewManagerTest : public testing::Test {
   DISALLOW_COPY_AND_ASSIGN(ViewManagerTest);
 };
 
+TEST_F(ViewManagerTest, SecondEmbedRoot) {
+  ASSERT_TRUE(EmbedRoot(view_manager_init_.get(), kTestServiceURL));
+  connection_->DoRunLoopUntilChangesCount(1);
+  EXPECT_EQ(kTestServiceURL, connection_->changes()[0].embed_url);
+}
+
 // Verifies client gets a valid id.
 TEST_F(ViewManagerTest, ValidId) {
   // TODO(beng): this should really have the URL of the application that