Fix warnings.

Source/Core/Elements/ElementProgressBar.cpp

@@ -161,7 +161,7 @@ void ElementProgressBar::OnResize()
 void ElementProgressBar::GenerateGeometry()
 {
 	// Warn the user when using the old approach of adding the 'fill-image' property to the 'fill' element.
-	if (const Property* property = fill->GetLocalProperty(PropertyId::FillImage))
+	if (fill->GetLocalProperty(PropertyId::FillImage))
 		Log::Message(Log::LT_WARNING, "Breaking change: The 'fill-image' property now needs to be set on the <progressbar> element, instead of its inner <fill> element. Please update your RCSS source to fix progress bars in this document.");
 
 	Vector2f render_size = fill_size;

Source/Core/StyleSheetParser.cpp

@@ -53,7 +53,7 @@ public:
  *  PropertySpecificationParser just passes the parsing to a property specification. Usually
  *    the main stylesheet specification, except for e.g. @decorator blocks.
 */
-class PropertySpecificationParser : public AbstractPropertyParser {
+class PropertySpecificationParser final : public AbstractPropertyParser {
 private:
 	// The dictionary to store the properties in.
 	PropertyDictionary& properties;
@@ -75,7 +75,7 @@ public:
  *    while its values are always rectangles. Thus, it must be parsed with a special "rectangle" parser
  *    for every name-value pair. We can probably optimize this for @performance.
 */
-class SpritesheetPropertyParser : public AbstractPropertyParser {
+class SpritesheetPropertyParser final : public AbstractPropertyParser {
 private:
 	String image_source;
 	SpriteDefinitionList sprite_definitions;