Make wxTextEntry::SetHint() work with all derived controls in wxOSX.

Previously, the method was only implemented in wxTextCtrl even though it used
wxTextEntry code to do the actual work. Move the implementation into
wxTextEntry.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/branches/WX_3_0_BRANCH@75122 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/osx/textctrl.h

@@ -74,10 +74,6 @@ public:
     virtual void MarkDirty();
     virtual void DiscardEdits();
 
-    // set the grayed out hint text
-    virtual bool SetHint(const wxString& hint);
-    virtual wxString GetHint() const;
-
     // text control under some platforms supports the text styles: these
     // methods apply the given text style to the given selection or to
     // set/get the style which will be used for all appended text
@@ -151,7 +147,6 @@ protected:
 
 private :
     wxMenu  *m_privateContextMenu;
-    wxString m_hintString;
 
     DECLARE_EVENT_TABLE()
 };