Fixes various issues with old UI settings code.

icc was quite unhappy with these classes and it's evident at looking at them
that they haven't gotten any love since they were slated for eventual deletion.

mythtv/libs/libmyth/settings.cpp

@@ -705,7 +705,7 @@ void ComboBoxSetting::setVisible(bool b)
     }
 }
 
-void ComboBoxSetting::setValue(QString newValue)
+void ComboBoxSetting::setValue(const QString &newValue)
 {
     for (uint i = 0; i < values.size(); i++)
     {
@@ -875,6 +875,20 @@ void DateSetting::setValue(const QDate& newValue) {
     Setting::setValue(newValue.toString(Qt::ISODate));
 }
 
+void DateSetting::setValue(const QString &newValue)
+{
+    QDate date = QDate::fromString(newValue, Qt::ISODate);
+    if (date.isValid())
+        setValue(date);
+}
+
+void TimeSetting::setValue(const QString &newValue)
+{
+    QTime time = QTime::fromString(newValue, Qt::ISODate);
+    if (time.isValid())
+        setValue(time);
+}
+
 QWidget* CheckBoxSetting::configWidget(ConfigurationGroup *cg, QWidget* parent,
                                        const char* widgetName) {
     widget = new MythCheckBox(parent, widgetName);