Git: Add diff options for show

Task-number: QTCREATORBUG-5262

Change-Id: I3e911fbb32c5d11cd46747b459c5b1a73c0a99b9
Reviewed-by: Tobias Hunger <tobias.hunger@nokia.com>

src/plugins/git/gitclient.cpp

@@ -171,7 +171,7 @@ private:
     const QString m_branchName;
 };
 
-class GitShowArgumentsWidget : public VCSBase::VCSBaseEditorParameterWidget
+class GitShowArgumentsWidget : public BaseGitDiffArgumentsWidget
 {
     Q_OBJECT
 
@@ -180,6 +180,7 @@ public:
                            const QString &directory,
                            const QStringList &args,
                            const QString &id) :
+        BaseGitDiffArgumentsWidget(client, directory, args),
         m_client(client),
         m_workingDirectory(directory),
         m_args(args),