[poincare] Proper virtual destructor for ExpressionLayout

poincare/include/poincare/expression_layout.h

@@ -8,6 +8,8 @@ extern "C" {
 class ExpressionLayout {
   public:
     ExpressionLayout(ExpressionLayout * parent);
+    virtual ~ExpressionLayout();
+
     void draw(KDPoint point);
     KDPoint origin();
     KDSize size();

poincare/src/layout/expression_layout.cpp

@@ -5,13 +5,11 @@
 ExpressionLayout::ExpressionLayout(ExpressionLayout * parent) :
   m_parent(parent),
   m_sized(false),
-  m_positioned(false) {
-    m_frame = (KDRect){
-      .x = 0,
-      .y = 0,
-      .width = 0,
-      .height = 0
-    };
+  m_positioned(false),
+  m_frame(KDRectZero) {
+}
+
+ExpressionLayout::~ExpressionLayout() {
 }
 
 KDPoint ExpressionLayout::origin() {