Makes the view manager notify the client of new roots correctly

Prior to this patch the server would not notify the client of a new
root if the client already knew about the root. Now it always
notifies.

Here's an example of this case: two nodes, A and B with B a child of
A and A the root for the client. If B is added as a root then
previously I would not send B in OnRootsAdded. Now I do.

BUG=365012
TEST=none
R=ben@chromium.org

Review URL: https://codereview.chromium.org/323413003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@276803 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 10 insertions, 3 deletions

diff --git a/mojo/services/view_manager/view_manager_connection.cc b/mojo/services/view_manager/view_manager_connection.cc
index 0c724bd..c3053c0d 100644
--- a/mojo/services/view_manager/view_manager_connection.cc
+++ b/mojo/services/view_manager/view_manager_connection.cc
@@ -436,10 +436,14 @@ bool ViewManagerConnection::AddRoots(
 
     did_add_root = true;
     roots_.insert(node_ids[i]);
+    Node* node = GetNode(NodeIdFromTransportId(node_ids[i]));
+    DCHECK(node);
     if (known_nodes_.count(node_ids[i]) == 0) {
-      Node* node = GetNode(NodeIdFromTransportId(node_ids[i]));
-      DCHECK(node);
       GetUnknownNodesFrom(node, &to_send);
+    } else {
+      // Even though the connection knows about the new root we need to tell it
+      // |node| is now a root.
+      to_send.push_back(node);
     }
   }
 
diff --git a/mojo/services/view_manager/view_manager_connection_unittest.cc b/mojo/services/view_manager/view_manager_connection_unittest.cc
index d9280d8..8cfc77a 100644
--- a/mojo/services/view_manager/view_manager_connection_unittest.cc
+++ b/mojo/services/view_manager/view_manager_connection_unittest.cc
@@ -1299,6 +1299,9 @@ TEST_F(ViewManagerConnectionTest, CantGetNodeTreeOfOtherRoots) {
 TEST_F(ViewManagerConnectionTest, ConnectTwice) {
   ASSERT_TRUE(connection_->CreateNode(BuildNodeId(1, 1)));
   ASSERT_TRUE(connection_->CreateNode(BuildNodeId(1, 2)));
+
+  ASSERT_TRUE(connection_->AddNode(BuildNodeId(1, 1), BuildNodeId(1, 2), 1));
+
   ASSERT_NO_FATAL_FAILURE(EstablishSecondConnection(false));
 
   // Try to connect again to 1,1, this should fail as already connected to that
@@ -1318,7 +1321,7 @@ TEST_F(ViewManagerConnectionTest, ConnectTwice) {
     const Changes changes(ChangesToDescription1(connection2_->changes()));
     ASSERT_EQ(1u, changes.size());
     EXPECT_EQ("OnRootsAdded", changes[0]);
-    EXPECT_EQ("[node=1,2 parent=null view=null]",
+    EXPECT_EQ("[node=1,2 parent=1,1 view=null]",
               ChangeNodeDescription(connection2_->changes()));
   }
 }