Qt5: No longer use fake user agent on google sites

QtWebKit version Qt5 is current enough to handle well
all google apps.

src/lib/other/useragentmanager.cpp

@@ -61,9 +61,11 @@ QString UserAgentManager::userAgentForUrl(const QUrl &url) const
         }
     }
 
+#if QT_VERSION < 0x050000
     if (host.contains(QLatin1String("google"))) {
         return m_fakeUserAgent;
     }
+#endif
 
     return m_globalUserAgent;
 }