Fix QNetworkRequest usage in WebEngineWidgets on Windows

Changing unused variable suppression in acceptNavigationRequest
is required for MSVC otherwise it fail with undefined type error.
Also adding more suppression for unused wariable warning.

Change-Id: Ic449973bc8166f18655e40bf57041b8f02869266
Reviewed-by: Jocelyn Turcotte <jocelyn.turcotte@digia.com>

src/webenginewidgets/api/qwebenginepage.h

@@ -562,7 +562,7 @@ protected:
     virtual QWebEnginePage *createWindow(WebWindowType type);
     virtual QObject *createPlugin(const QString &classid, const QUrl &url, const QStringList &paramNames, const QStringList &paramValues) { Q_UNUSED(classid); Q_UNUSED(url); Q_UNUSED(paramNames); Q_UNUSED(paramValues); Q_UNREACHABLE(); return 0; }
 
-    virtual bool acceptNavigationRequest(QWebEngineFrame *frame, const QNetworkRequest &request, NavigationType type) { Q_UNUSED(frame); Q_UNUSED(request); Q_UNUSED(type); Q_UNREACHABLE(); return false; }
+    virtual bool acceptNavigationRequest(QWebEngineFrame *frame, const QNetworkRequest &request, NavigationType type) { Q_UNUSED(frame); Q_UNUSED(&request); Q_UNUSED(type); Q_UNREACHABLE(); return false; }
     virtual QStringList chooseFiles(FileSelectionMode mode, const QStringList &oldFiles, const QStringList &acceptedMimeTypes);
     virtual void javaScriptAlert(QWebEngineFrame *originatingFrame, const QString& msg);
     virtual bool javaScriptConfirm(QWebEngineFrame *originatingFrame, const QString& msg);

src/webenginewidgets/api/qwebenginepage_p.h

@@ -87,7 +87,7 @@ public:
     virtual void didRunJavaScript(const QVariant& result, quint64 requestId) Q_DECL_OVERRIDE;
     virtual void didFetchDocumentMarkup(const QString& result, quint64 requestId) Q_DECL_OVERRIDE;
     virtual void didFetchDocumentInnerText(const QString& result, quint64 requestId) Q_DECL_OVERRIDE;
-    virtual void passOnFocus(bool reverse) Q_DECL_OVERRIDE { };
+    virtual void passOnFocus(bool reverse) Q_DECL_OVERRIDE { Q_UNUSED(reverse); };
 
     virtual void javaScriptConsoleMessage(int level, const QString& message, int lineNumber, const QString& sourceID) Q_DECL_OVERRIDE;