riched20: Use EM_GETTEXTLENGTHEX to implement WM_GETTEXTLENGTH.

dlls/riched20/editor.c

@@ -3969,10 +3969,8 @@ LRESULT ME_HandleMessage(ME_TextEditor *editor, UINT msg, WPARAM wParam,
   case WM_GETTEXTLENGTH:
   {
     GETTEXTLENGTHEX how;
-
-    /* CR/LF conversion required in 2.0 mode, verbatim in 1.0 mode */
     how.flags = GTL_CLOSE | (editor->bEmulateVersion10 ? 0 : GTL_USECRLF) | GTL_NUMCHARS;
-    how.codepage = unicode ? CP_UNICODE : CP_ACP;
+    how.codepage = CP_UNICODE;
     return ME_GetTextLengthEx(editor, &how);
   }
   case EM_GETTEXTLENGTHEX:

dlls/riched20/txthost.c

@@ -801,6 +801,15 @@ static LRESULT RichEditWndProc_common( HWND hwnd, UINT msg, WPARAM wparam,
             FillRect( hdc, &rc, editor->hbrBackground );
         return 1;
     }
+    case WM_GETTEXTLENGTH:
+    {
+        GETTEXTLENGTHEX params;
+
+        params.flags = GTL_CLOSE | (host->emulate_10 ? 0 : GTL_USECRLF) | GTL_NUMCHARS;
+        params.codepage = unicode ? CP_UNICODE : CP_ACP;
+        hr = ITextServices_TxSendMessage( host->text_srv, EM_GETTEXTLENGTHEX, (WPARAM)&params, 0, &res );
+        break;
+    }
     case WM_PAINT:
     {
         HDC hdc;