OS X: Welcome/QQuickWidget fixes

The rendered text is still ugly, but the fuzzy text is better than the
alternative currently.

Change-Id: Id9e54fb406ee964e0b9b5c40b7a8108b45c15f85
Task-number: QTBUG-42861
Reviewed-by: Eike Ziller <eike.ziller@theqtcompany.com>

share/qtcreator/welcomescreen/widgets/NativeText.qml

@@ -31,7 +31,7 @@
 import QtQuick 2.1
 
 Text {
-    renderType: Text.NativeRendering
+    renderType: useNativeText ? Text.NativeRendering : Text.QtRendering
     Accessible.name: text
     Accessible.role: Accessible.StaticText
 }

src/plugins/help/macwebkithelpviewer.mm

@@ -415,6 +415,9 @@ MacWebKitHelpWidget::MacWebKitHelpWidget(MacWebKitHelpViewer *parent)
 {
     AutoreleasePool pool; Q_UNUSED(pool)
     d->m_webView = [[MyWebView alloc] init];
+    // Turn layered rendering on.
+    // Otherwise the WebView will render empty after any QQuickWidget was shown.
+    d->m_webView.wantsLayer = YES;
     d->m_frameLoadDelegate = [[FrameLoadDelegate alloc] initWithMainFrame:d->m_webView.mainFrame
                                                                    viewer:parent];
     [d->m_webView setFrameLoadDelegate:d->m_frameLoadDelegate];

src/plugins/welcome/welcomeplugin.cpp

@@ -155,7 +155,6 @@ WelcomeMode::WelcomeMode()
 #endif // USE_QUICK_WIDGET
 
     connect(PluginManager::instance(), SIGNAL(objectAdded(QObject*)), SLOT(welcomePluginAdded(QObject*)));
-
     setWidget(m_modeWidget);
 }
 
@@ -260,6 +259,13 @@ void WelcomeMode::initPlugins()
     connect(Core::ICore::instance(), &Core::ICore::themeChanged, this, &WelcomeMode::onThemeChanged);
     ctx->setContextProperty(QLatin1String("creatorTheme"), &m_themeProperties);
 
+#if defined(USE_QUICK_WIDGET)
+    bool useNativeText = !Utils::HostOsInfo::isMacHost();
+#else
+    bool useNativeText = true;
+#endif
+    ctx->setContextProperty(QLatin1String("useNativeText"), useNativeText);
+
     QString path = resourcePath() + QLatin1String("/welcomescreen/welcomescreen.qml");
 
     // finally, load the root page