ClangFormat: Split formatting on save into a separate editor action

Do not combine formatting on save with other action happening
before it.

Fixes: QTCREATORBUG-22145
Change-Id: I435115400b9bef1377fac992b4952d3701fca3ac
Reviewed-by: Eike Ziller <eike.ziller@qt.io>

src/plugins/cppeditor/cppeditordocument.cpp

@@ -475,7 +475,7 @@ bool CppEditorDocument::save(QString *errorString, const QString &fileName, bool
 
         if (!editedRanges.empty()) {
             QTextCursor cursor(document());
-            cursor.joinPreviousEditBlock();
+            cursor.beginEditBlock();
             indenter()->format(editedRanges);
             cursor.endEditBlock();
         }