Add wxPoint::IsFullySpecified() and SetDefaults().

These methods do the same thing as wxSize methods with the same names and are
useful for the same reasons.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@65259 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/gdicmn.h

@@ -524,6 +524,18 @@ public:
 
     wxPoint& operator+=(const wxSize& s) { x += s.GetWidth(); y += s.GetHeight(); return *this; }
     wxPoint& operator-=(const wxSize& s) { x -= s.GetWidth(); y -= s.GetHeight(); return *this; }
+
+    // check if both components are set/initialized
+    bool IsFullySpecified() const { return x != wxDefaultCoord && y != wxDefaultCoord; }
+
+    // fill in the unset components with the values from the other point
+    void SetDefaults(const wxPoint& pt)
+    {
+        if ( x == wxDefaultCoord )
+            x = pt.x;
+        if ( y == wxDefaultCoord )
+            y = pt.y;
+    }
 };