mus: Implement interwindow drag and drop

services/ui/ws/test_utils.cc

Index: services/ui/ws/test_utils.cc
diff --git a/services/ui/ws/test_utils.cc b/services/ui/ws/test_utils.cc
index c088331de68465d076798738e78d24cd07d5a380..f6ef10cdace2f3a49f060d1c8db4a8ec135f2a5d 100644
--- a/services/ui/ws/test_utils.cc
+++ b/services/ui/ws/test_utils.cc
@@ -352,6 +352,32 @@ void TestWindowTreeClient::OnWindowPredefinedCursorChanged(
   tracker_.OnWindowPredefinedCursorChanged(window_id, cursor_id);
 }
 
+void TestWindowTreeClient::OnDragStart(
+    Id window_id,
+    mojo::Map<mojo::String, mojo::Array<uint8_t>> mime_data) {}
+
+void TestWindowTreeClient::OnDragEnter(uint32_t window,
+                                       uint32_t key_state,
+                                       const gfx::Point& position,
+                                       uint32_t effect_bitmask,
+                                       const OnDragEnterCallback& callback) {}
+
+void TestWindowTreeClient::OnDragOver(uint32_t window,
+                                      uint32_t key_state,
+                                      const gfx::Point& position,
+                                      uint32_t effect_bitmask,
+                                      const OnDragOverCallback& callback) {}
+
+void TestWindowTreeClient::OnDragLeave(uint32_t window) {}
+
+void TestWindowTreeClient::OnDragDrop(uint32_t window,
+                                      uint32_t key_state,
+                                      const gfx::Point& position,
+                                      uint32_t effect_bitmask,
+                                      const OnDragDropCallback& callback) {}
+
+void TestWindowTreeClient::OnDragFinish(Id window_id) {}
+
 void TestWindowTreeClient::OnChangeCompleted(uint32_t change_id, bool success) {
   if (record_on_change_completed_)
     tracker_.OnChangeCompleted(change_id, success);