chromeos: implements StackAbove for ws2

BUG=837700
TEST=covered by tests
TBR=tsepez@chromium.org

Change-Id: I9d2fc168a33e9daf00ca9ca9f8b03989122cb848
Reviewed-on: https://chromium-review.googlesource.com/1089201Reviewed-by: Scott Violet <sky@chromium.org>
Reviewed-by: Michael Wasserman <msw@chromium.org>
Commit-Queue: Scott Violet <sky@chromium.org>
Cr-Commit-Position: refs/heads/master@{#565004}

services/ui/public/interfaces/window_tree.mojom

@@ -319,7 +319,9 @@ interface WindowTree {
   DeactivateWindow(uint64 window_id);
 
   // Stacks the window |above_id| above |below_id|. These two windows must
-  // share the same parent.
+  // share the same parent. This function is intended for use with top-levels
+  // only. For non-top-levels, use ReorderWindow().
+  // TODO(sky): unify this and ReorderWindow(). https://crbug.com/850133.
   StackAbove(uint32 change_id, uint64 above_id, uint64 below_id);
 
   // Stacks the window above all sibling windows.

services/ui/ws2/window_service_client.cc

@@ -843,6 +843,25 @@ bool WindowServiceClient::SetFocusImpl(const ClientWindowId& window_id) {
   return focus_handler_.SetFocus(GetWindowByClientId(window_id));
 }
 
+bool WindowServiceClient::StackAboveImpl(
+    const ClientWindowId& above_window_id,
+    const ClientWindowId& below_window_id) {
+  DVLOG(3) << "StackAbove above_window_id=" << above_window_id
+           << " below_window_id=" << below_window_id;
+  aura::Window* above_window = GetWindowByClientId(above_window_id);
+  aura::Window* below_window = GetWindowByClientId(below_window_id);
+  // This function only applies to top-levels.
+  if (!IsClientCreatedWindow(above_window) ||
+      !IsClientCreatedWindow(below_window) || !IsTopLevel(above_window) ||
+      !IsTopLevel(below_window) || !above_window->parent() ||
+      above_window->parent() != below_window->parent()) {
+    DVLOG(1) << "StackAbove failed (invalid windows)";
+    return false;
+  }
+  above_window->parent()->StackChildAbove(above_window, below_window);
+  return true;
+}
+
 bool WindowServiceClient::StackAtTopImpl(const ClientWindowId& window_id) {
   DVLOG(3) << "StackAtTop window_id= " << window_id;
 
@@ -1265,7 +1284,9 @@ void WindowServiceClient::DeactivateWindow(Id window_id) {
 void WindowServiceClient::StackAbove(uint32_t change_id,
                                      Id above_id,
                                      Id below_id) {
-  NOTIMPLEMENTED_LOG_ONCE();
+  const bool result = StackAboveImpl(MakeClientWindowId(above_id),
+                                     MakeClientWindowId(below_id));
+  window_tree_client_->OnChangeCompleted(change_id, result);
 }
 
 void WindowServiceClient::StackAtTop(uint32_t change_id, Id window_id) {

services/ui/ws2/window_service_client.h

@@ -235,6 +235,8 @@ class COMPONENT_EXPORT(WINDOW_SERVICE) WindowServiceClient
                          mojom::OrderDirection direction);
   std::vector<aura::Window*> GetWindowTreeImpl(const ClientWindowId& window_id);
   bool SetFocusImpl(const ClientWindowId& window_id);
+  bool StackAboveImpl(const ClientWindowId& above_window_id,
+                      const ClientWindowId& below_window_id);
   bool StackAtTopImpl(const ClientWindowId& window_id);
 
   void GetWindowTreeRecursive(aura::Window* window,

services/ui/ws2/window_service_client_test_helper.cc

@@ -117,10 +117,9 @@ Embedding* WindowServiceClientTestHelper::Embed(
     mojom::WindowTreeClientPtr client_ptr,
     mojom::WindowTreeClient* client,
     uint32_t embed_flags) {
-  if (!window_service_client_->EmbedImpl(
-          window_service_client_->MakeClientWindowId(
-              TransportIdForWindow(window)),
-          std::move(client_ptr), client, embed_flags)) {
+  if (!window_service_client_->EmbedImpl(ClientWindowIdForWindow(window),
+                                         std::move(client_ptr), client,
+                                         embed_flags)) {
     return nullptr;
   }
   return ClientWindow::GetMayBeNull(window)->embedding();
@@ -139,9 +138,16 @@ void WindowServiceClientTestHelper::OnWindowInputEventAck(
   window_service_client_->OnWindowInputEventAck(event_id, result);
 }
 
+bool WindowServiceClientTestHelper::StackAbove(aura::Window* above_window,
+                                               aura::Window* below_window) {
+  return window_service_client_->StackAboveImpl(
+      ClientWindowIdForWindow(above_window),
+      ClientWindowIdForWindow(below_window));
+}
+
 bool WindowServiceClientTestHelper::StackAtTop(aura::Window* window) {
   return window_service_client_->StackAtTopImpl(
-      window_service_client_->MakeClientWindowId(TransportIdForWindow(window)));
+      ClientWindowIdForWindow(window));
 }
 
 Id WindowServiceClientTestHelper::TransportIdForWindow(aura::Window* window) {
@@ -150,8 +156,7 @@ Id WindowServiceClientTestHelper::TransportIdForWindow(aura::Window* window) {
 }
 
 bool WindowServiceClientTestHelper::SetFocus(aura::Window* window) {
-  return window_service_client_->SetFocusImpl(
-      window_service_client_->MakeClientWindowId(TransportIdForWindow(window)));
+  return window_service_client_->SetFocusImpl(ClientWindowIdForWindow(window));
 }
 
 void WindowServiceClientTestHelper::SetCanFocus(aura::Window* window,

services/ui/ws2/window_service_client_test_helper.h

@@ -93,6 +93,7 @@ class WindowServiceClientTestHelper {
   bool SetFocus(aura::Window* window);
   void SetCanFocus(aura::Window* window, bool can_focus);
   void OnWindowInputEventAck(uint32_t event_id, mojom::EventResult result);
+  bool StackAbove(aura::Window* above_window, aura::Window* below_window);
   bool StackAtTop(aura::Window* window);
 
   Id TransportIdForWindow(aura::Window* window);

services/ui/ws2/window_service_client_unittest.cc

@@ -1069,6 +1069,57 @@ TEST(WindowServiceClientTest, ReorderWindow) {
       top_level, window2, mojom::OrderDirection::ABOVE));
 }
 
+TEST(WindowServiceClientTest, StackAbove) {
+  // Create two top-levels.
+  WindowServiceTestSetup setup;
+  aura::Window* top_level1 = setup.client_test_helper()->NewTopLevelWindow();
+  ASSERT_TRUE(top_level1);
+  aura::Window* top_level2 = setup.client_test_helper()->NewTopLevelWindow();
+  ASSERT_TRUE(top_level2);
+  ASSERT_TRUE(top_level1->parent());
+  ASSERT_EQ(top_level1->parent(), top_level2->parent());
+  ASSERT_EQ(2u, top_level2->parent()->children().size());
+
+  // 1 on top of 2.
+  EXPECT_TRUE(setup.client_test_helper()->StackAbove(top_level1, top_level2));
+  EXPECT_EQ(top_level2, top_level2->parent()->children()[0]);
+  EXPECT_EQ(top_level1, top_level2->parent()->children()[1]);
+
+  // Repeat, should still succeed and nothing should change.
+  EXPECT_TRUE(setup.client_test_helper()->StackAbove(top_level1, top_level2));
+  EXPECT_EQ(top_level2, top_level2->parent()->children()[0]);
+  EXPECT_EQ(top_level1, top_level2->parent()->children()[1]);
+
+  // 2 on top of 1.
+  EXPECT_TRUE(setup.client_test_helper()->StackAbove(top_level2, top_level1));
+  EXPECT_EQ(top_level1, top_level2->parent()->children()[0]);
+  EXPECT_EQ(top_level2, top_level2->parent()->children()[1]);
+
+  // 1 on top of 2, using WindowTree interface, which should result in an ack.
+  setup.changes()->clear();
+  uint32_t change_id = 102;
+  setup.client_test_helper()->window_tree()->StackAbove(
+      change_id, setup.client_test_helper()->TransportIdForWindow(top_level1),
+      setup.client_test_helper()->TransportIdForWindow(top_level2));
+  EXPECT_EQ("ChangeCompleted id=102 success=true",
+            SingleChangeToDescription(*setup.changes()));
+  setup.changes()->clear();
+  EXPECT_EQ(top_level2, top_level2->parent()->children()[0]);
+  EXPECT_EQ(top_level1, top_level2->parent()->children()[1]);
+
+  // Using invalid id should fail.
+  setup.client_test_helper()->window_tree()->StackAbove(
+      change_id, setup.client_test_helper()->TransportIdForWindow(top_level1),
+      kInvalidTransportId);
+  EXPECT_EQ("ChangeCompleted id=102 success=false",
+            SingleChangeToDescription(*setup.changes()));
+
+  // Using non-top-level should fail.
+  aura::Window* non_top_level_window = setup.client_test_helper()->NewWindow();
+  EXPECT_FALSE(
+      setup.client_test_helper()->StackAbove(top_level1, non_top_level_window));
+}
+
 }  // namespace
 }  // namespace ws2
 }  // namespace ui