fix the memory corruption in multiline controls due to wrong WrapLines() implementation [backport of rev 45343]

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/branches/WX_2_8_BRANCH@47170 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/univ/textctrl.h

@@ -234,9 +234,8 @@ public:
     virtual bool Enable(bool enable = true);
 
     // more readable flag testing methods
-    bool IsPassword() const { return (GetWindowStyle() & wxTE_PASSWORD) != 0; }
-    bool WrapLines() const
-        { return !IsSingleLine() && !(GetWindowStyle() & wxHSCROLL); }
+    bool IsPassword() const { return HasFlag(wxTE_PASSWORD); }
+    bool WrapLines() const { return m_wrapLines; }
 
     // only for wxStdTextCtrlInputHandler
     void RefreshSelection();
@@ -500,7 +499,8 @@ private:
     // flags
     bool m_isModified:1,
          m_isEditable:1,
-         m_hasCaret:1;
+         m_hasCaret:1,
+         m_wrapLines:1; // can't be changed after creation
 
     // the rectangle (in client coordinates) to draw text inside
     wxRect m_rectText;