Fixes to WindowTreeHostMus

ui/aura/test/mus/test_window_tree.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/aura/test/mus/test_window_tree.h"
 
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace aura {
 
@@ skipping 67 matching lines @@
   for (auto iter = changes_.begin(); iter != changes_.end(); ++iter) {
     if (iter->type != type)
       continue;
     *change_id = iter->id;
     changes_.erase(iter);
     return true;
   }
   return false;
 }
 
+size_t TestWindowTree::GetChangeCountForType(WindowTreeChangeType type) {
+  size_t count = 0;
+  for (const auto& change : changes_) {
+    if (change.type == type)
+      ++count;
+  }
+  return count;
+}
+
 void TestWindowTree::OnChangeReceived(uint32_t change_id,
                                       WindowTreeChangeType type) {
   changes_.push_back({type, change_id});
 }
 
 void TestWindowTree::NewWindow(
     uint32_t change_id,
     uint32_t window_id,
     mojo::Map<mojo::String, mojo::Array<uint8_t>> properties) {
   last_new_window_properties_ = std::move(properties);
@@ skipping 164 matching lines @@
 void TestWindowTree::PerformWindowMove(uint32_t change_id,
                                        uint32_t window_id,
                                        ui::mojom::MoveLoopSource source,
                                        const gfx::Point& cursor_location) {
   OnChangeReceived(change_id);
 }
 
 void TestWindowTree::CancelWindowMove(uint32_t window_id) {}
 
 }  // namespace aura