Revert "Code model: Update on changes from the versioning system."

This reverts commit 7aa2411693.
It breaks the code model updates completely. So reverting this change
until we have the right thing.

Reviewed-by: Roberto Raggi

src/plugins/git/gitplugin.h

@@ -59,7 +59,6 @@ namespace Git {
 namespace Internal {
 
 class GitPlugin;
-class GitVersionControl;
 class GitClient;
 class ChangeSelectionDialog;
 class GitSubmitEditor;
@@ -97,7 +96,6 @@ public:
     void setSettings(const GitSettings &s);
 
     GitClient *gitClient() const;
-    GitVersionControl *versionControl() const;
 
 public slots:
     void updateActions();
@@ -161,7 +159,6 @@ private:
     QAction *m_branchListAction;
 
     GitClient                   *m_gitClient;
-    GitVersionControl           *m_versionControl;
     ChangeSelectionDialog       *m_changeSelectionDialog;
     QString                     m_submitRepository;
     QStringList                 m_submitOrigCommitFiles;