Fix inserting an element of wxArrayString itself back into it.

Do the insertion/addition before deallocating the old memory to allow things
like array.Add(array[0]) to work correctly.

Closes #2290.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/branches/WX_3_0_BRANCH@76907 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/arrstr.h

@@ -364,7 +364,10 @@ protected:
   void Copy(const wxArrayString& src);  // copies the contents of another array
 
 private:
-  void Grow(size_t nIncrement = 0);     // makes array bigger if needed
+  // Allocate the new buffer big enough to hold m_nCount + nIncrement items and
+  // return the pointer to the old buffer, which must be deleted by the caller
+  // (if the old buffer is big enough, just return NULL).
+  wxString *Grow(size_t nIncrement);
 
   size_t  m_nSize,    // current size of the array
           m_nCount;   // current number of elements