msbuild: use the moc dispatcher from Qt's vstools

The new method supports build parallelism and cleaner
integration into msbuild dependency flows.

Source/VSProps/qtmoc_cl.targets

@@ -0,0 +1,49 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+    *****************************************************************************
+    **
+    ** Copyright (C) 2019 The Qt Company Ltd.
+    ** Contact: https://www.qt.io/licensing/
+    **
+    ** This file is part of the Qt VS Tools.
+    **
+    ** $QT_BEGIN_LICENSE:GPL-EXCEPT$
+    ** Commercial License Usage
+    ** Licensees holding valid commercial Qt licenses may use this file in
+    ** accordance with the commercial license agreement provided with the
+    ** Software or, alternatively, in accordance with the terms contained in
+    ** a written agreement between you and The Qt Company. For licensing terms
+    ** and conditions see https://www.qt.io/terms-conditions. For further
+    ** information use the contact form at https://www.qt.io/contact-us.
+    **
+    ** GNU General Public License Usage
+    ** Alternatively, this file may be used under the terms of the GNU
+    ** General Public License version 3 as published by the Free Software
+    ** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
+    ** included in the packaging of this file. Please review the following
+    ** information to ensure the GNU General Public License requirements will
+    ** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+    **
+    ** $QT_END_LICENSE$
+    **
+    *****************************************************************************
+-->
+<Project xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <Target Name="QtMocOverrideCpp" DependsOnTargets="QtMocPrepare;QtGetDefaultClCompile"
+    Inputs="%(QtMoc.Identity)" Outputs="@(QtMoc->'####### Don't skip this target #######')">
+
+    <Message Importance="High" Condition="'$(QtDebug)' == 'true'"
+      Text="## QtMocOverrideCpp @(QtMoc)" />
+    <!--
+      NOTE: This implementation was a template, which has been manually edited
+      for dolphin-emu specific behavior (carries over defines but not includes)
+    -->
+    <ItemGroup>
+      <QtMoc>
+        <IncludePath></IncludePath>
+        <Define>%(ClCompile.PreprocessorDefinitions)</Define>
+        <Undefine></Undefine>
+      </QtMoc>
+    </ItemGroup>
+  </Target>
+</Project>