Sheet: modernize C++: use default member init

src/Mod/Spreadsheet/App/PropertySheet.cpp

@@ -253,7 +253,6 @@ Cell * PropertySheet::createCell(CellAddress address)
 
 PropertySheet::PropertySheet(Sheet *_owner)
     : owner(_owner)
-    , updateCount(0)
 {
 }
 

src/Mod/Spreadsheet/App/PropertySheet.h

@@ -298,7 +298,7 @@ private:
 
     std::map<const App::DocumentObject*, boost::signals2::scoped_connection> depConnections;
 
-    int updateCount;
+    int updateCount = 0;
     bool restoring = false;
 };
 

src/Mod/Spreadsheet/App/SheetObserver.cpp

@@ -39,7 +39,6 @@ using namespace App;
 
 SheetObserver::SheetObserver(App::Document * document, PropertySheet *_sheet)
     : DocumentObserver(document)
-    , refCount(1)
     , sheet(_sheet)
 {
 }

src/Mod/Spreadsheet/App/SheetObserver.h

@@ -42,7 +42,7 @@ public:
     App::Document* getDocument() const { return App::DocumentObserver::getDocument(); }
 private:
     std::set<std::string> isUpdating;
-    unsigned int refCount;
+    unsigned int refCount{1};
     PropertySheet * sheet;
 };