Do not use deprecated Qt functionality.

Replace all* remaining deprecated Qt 4 functions with
their Qt 5 counterparts. This means we no longer need to
define the QT_DISABLE_DEPRECATED_BEFORE macro.
This patch is relatively small because most source-compatible
changes of this kind have been done before.

* The one exception is the QmlDesigner, which uses QWeakPointer
in a deprecated way all over the place.

Change-Id: Id4b839c6685f3b5bdf2b89137f95231758ec53c7
Reviewed-by: Eike Ziller <eike.ziller@digia.com>
Reviewed-by: hjk <hjk121@nokiamail.com>

src/plugins/coreplugin/externaltool.cpp

@@ -316,7 +316,7 @@ static void localizedText(const QStringList &locales, QXmlStreamReader *reader,
         if (*currentLocale < 0 && currentText->isEmpty()) {
             *currentText = QCoreApplication::translate("Core::Internal::ExternalTool",
                                                        reader->readElementText().toUtf8().constData(),
-                                                       "", QCoreApplication::UnicodeUTF8);
+                                                       "");
         } else {
             reader->skipCurrentElement();
         }