mash: make Env::last_mouse_location() accurate for Mus

ui/aura/test/aura_test_helper.cc

 // Copyright (c) 2012 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/aura_test_helper.h"
 
 #include "base/memory/ptr_util.h"
 #include "base/message_loop/message_loop.h"
 #include "base/run_loop.h"
 #include "ui/aura/client/default_capture_client.h"
@@ skipping 81 matching lines @@
       (mode_ == Mode::LOCAL) ? Env::Mode::LOCAL : Env::Mode::MUS;
   if (mode_ == Mode::MUS_CREATE_WINDOW_TREE_CLIENT)
     InitWindowTreeClient();
   if (!Env::GetInstanceDontCreate())
     env_ = Env::CreateInstance(env_mode);
   EnvTestHelper env_helper;
   // Always reset the mode. This really only matters for if Env was created
   // above.
   env_helper.SetMode(env_mode);
   env_helper.SetWindowTreeClient(window_tree_client_);
+  // Tests assume they can set the mouse location on Env() and have it reflected
+  // in tests.
+  env_helper.SetAlwaysUseLastMouseLocation(true);
   Env::GetInstance()->SetActiveFocusClient(focus_client_.get(), nullptr);
   Env::GetInstance()->set_context_factory(context_factory);
   Env::GetInstance()->set_context_factory_private(context_factory_private);
   // Unit tests generally don't want to query the system, rather use the state
   // from RootWindow.
   env_helper.SetInputStateLookup(nullptr);
   env_helper.ResetEventState();
 
   ui::InitializeInputMethodForTesting();
 
@@ skipping 64 matching lines @@
 
 void AuraTestHelper::InitWindowTreeClient() {
   window_tree_client_setup_ = base::MakeUnique<TestWindowTreeClientSetup>();
   window_tree_client_setup_->InitForWindowManager(window_tree_delegate_,
                                                   window_manager_delegate_);
   window_tree_client_ = window_tree_client_setup_->window_tree_client();
 }
 
 }  // namespace test
 }  // namespace aura