riched20: Use helpers in the cursor to start/end functions.

dlls/riched20/caret.c

@@ -26,15 +26,15 @@ WINE_DEFAULT_DEBUG_CHANNEL(richedit);
 
 void ME_SetCursorToStart(ME_TextEditor *editor, ME_Cursor *cursor)
 {
-  cursor->pPara = editor->pBuffer->pFirst->member.para.next_para;
-  cursor->pRun = ME_FindItemFwd(cursor->pPara, diRun);
+  cursor->pPara = para_get_di( editor_first_para( editor ) );
+  cursor->pRun = run_get_di( para_first_run( &cursor->pPara->member.para ) );
   cursor->nOffset = 0;
 }
 
 static void ME_SetCursorToEnd(ME_TextEditor *editor, ME_Cursor *cursor, BOOL final_eop)
 {
-  cursor->pPara = editor->pBuffer->pLast->member.para.prev_para;
-  cursor->pRun = ME_FindItemBack(editor->pBuffer->pLast, diRun);
+  cursor->pPara = para_get_di( para_prev( editor_end_para( editor ) ) );
+  cursor->pRun = run_get_di( para_end_run( &cursor->pPara->member.para ) );
   cursor->nOffset = final_eop ? cursor->pRun->member.run.len : 0;
 }
 

dlls/riched20/editor.c

@@ -285,6 +285,12 @@ ME_Paragraph *editor_first_para( ME_TextEditor *editor )
     return para_next( &editor->pBuffer->pFirst->member.para );
 }
 
+/* Note, returns the diTextEnd sentinel paragraph */
+ME_Paragraph *editor_end_para( ME_TextEditor *editor )
+{
+    return &editor->pBuffer->pLast->member.para;
+}
+
 static LRESULT ME_StreamInText(ME_TextEditor *editor, DWORD dwFormat, ME_InStream *stream, ME_Style *style)
 {
   WCHAR *pText;

dlls/riched20/editor.h

@@ -273,6 +273,7 @@ void ME_ReplaceSel(ME_TextEditor *editor, BOOL can_undo, const WCHAR *str, int l
 int set_selection( ME_TextEditor *editor, int to, int from ) DECLSPEC_HIDDEN;
 HRESULT editor_copy_or_cut( ME_TextEditor *editor, BOOL cut, ME_Cursor *start, int count,
                             IDataObject **data_out ) DECLSPEC_HIDDEN;
+ME_Paragraph *editor_end_para( ME_TextEditor *editor ) DECLSPEC_HIDDEN;
 ME_Paragraph *editor_first_para( ME_TextEditor *editor ) DECLSPEC_HIDDEN;
 
 /* table.c */