Vcs: Move responsibility to set editor parameters to editor factory

So it doesn't need to be named twice in the editor factory setup.

This intentially includes a de-optimiztion: storing the parameters
by value, not by pointer. That's more natural, does not need to
keep the parameters alive on the caller side, and it's uncritical
in this context.

Change-Id: I92867d3f2f75c38911ae82d3eeb4759cba71b723
Reviewed-by: Orgad Shaneh <orgads@gmail.com>

src/plugins/mercurial/mercurialplugin.cpp

@@ -256,8 +256,7 @@ MercurialPluginPrivate::MercurialPluginPrivate()
     for (auto &editor : editorParameters)
         new VcsEditorFactory(&editor, widgetCreator, describeFunc, this);
 
-    new VcsSubmitEditorFactory(&submitEditorParameters,
-        []() { return new CommitEditor(&submitEditorParameters); }, this);
+    new VcsSubmitEditorFactory(submitEditorParameters, [] { return new CommitEditor; }, this);
 
     const QString prefix = QLatin1String("hg");
     m_commandLocator = new Core::CommandLocator("Mercurial", prefix, prefix, this);