Support wasm components installation (#55)

* Support for WebAssembler

- Qt 5.12 provide tech preview for wasm, and 5.13 and later it supports.

Signed-off-by: Hiroshi Miura <miurahr@linux.com>

tests/openglwindow/openglwindow.cpp

@@ -0,0 +1,166 @@
+/****************************************************************************
+**
+** Copyright (C) 2016 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the documentation of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** 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.
+**
+** BSD License Usage
+** Alternatively, you may use this file under the terms of the BSD license
+** as follows:
+**
+** "Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+**   * Redistributions of source code must retain the above copyright
+**     notice, this list of conditions and the following disclaimer.
+**   * Redistributions in binary form must reproduce the above copyright
+**     notice, this list of conditions and the following disclaimer in
+**     the documentation and/or other materials provided with the
+**     distribution.
+**   * Neither the name of The Qt Company Ltd nor the names of its
+**     contributors may be used to endorse or promote products derived
+**     from this software without specific prior written permission.
+**
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "openglwindow.h"
+
+#include <QtCore/QCoreApplication>
+
+#include <QtGui/QOpenGLContext>
+#include <QtGui/QOpenGLPaintDevice>
+#include <QtGui/QPainter>
+
+//! [1]
+OpenGLWindow::OpenGLWindow(QWindow *parent)
+    : QWindow(parent)
+    , m_animating(false)
+    , m_context(0)
+    , m_device(0)
+{
+    setSurfaceType(QWindow::OpenGLSurface);
+}
+//! [1]
+
+OpenGLWindow::~OpenGLWindow()
+{
+    delete m_device;
+}
+//! [2]
+void OpenGLWindow::render(QPainter *painter)
+{
+    Q_UNUSED(painter);
+}
+
+void OpenGLWindow::initialize()
+{
+}
+
+void OpenGLWindow::render()
+{
+    if (!m_device)
+        m_device = new QOpenGLPaintDevice;
+
+    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);
+
+    m_device->setSize(size() * devicePixelRatio());
+    m_device->setDevicePixelRatio(devicePixelRatio());
+
+    QPainter painter(m_device);
+    render(&painter);
+}
+//! [2]
+
+//! [3]
+void OpenGLWindow::renderLater()
+{
+    requestUpdate();
+}
+
+bool OpenGLWindow::event(QEvent *event)
+{
+    switch (event->type()) {
+    case QEvent::UpdateRequest:
+        renderNow();
+        return true;
+    default:
+        return QWindow::event(event);
+    }
+}
+
+void OpenGLWindow::exposeEvent(QExposeEvent *event)
+{
+    Q_UNUSED(event);
+
+    if (isExposed())
+        renderNow();
+}
+//! [3]
+
+//! [4]
+void OpenGLWindow::renderNow()
+{
+    if (!isExposed())
+        return;
+
+    bool needsInitialize = false;
+
+    if (!m_context) {
+        m_context = new QOpenGLContext(this);
+        m_context->setFormat(requestedFormat());
+        m_context->create();
+
+        needsInitialize = true;
+    }
+
+    m_context->makeCurrent(this);
+
+    if (needsInitialize) {
+        initializeOpenGLFunctions();
+        initialize();
+    }
+
+    render();
+
+    m_context->swapBuffers(this);
+
+    if (m_animating)
+        renderLater();
+}
+//! [4]
+
+//! [5]
+void OpenGLWindow::setAnimating(bool animating)
+{
+    m_animating = animating;
+
+    if (animating)
+        renderLater();
+}
+//! [5]
+