[libxml++/libxml++-3.0] Examples: Make some methods static.

[Murray Cumming <murrayc src gnome org>]

commit 2af973ff59b2151e0783bbe4155816ce88d0c8b0
Author: Murray Cumming <murrayc murrayc com>
Date:   Mon Dec 12 09:16:11 2016 +0100

    Examples: Make some methods static.
    
    Noticed by cppcheck.

 examples/dom_update_namespace/main.cc |    6 +++---
 1 files changed, 3 insertions(+), 3 deletions(-)
---
diff --git a/examples/dom_update_namespace/main.cc b/examples/dom_update_namespace/main.cc
index 3c47a4a..1e35003 100644
--- a/examples/dom_update_namespace/main.cc
+++ b/examples/dom_update_namespace/main.cc
@@ -32,12 +32,12 @@ class Tests
 
   protected:
     template<typename RefType, typename ValueType>
-    void assert_equal(const RefType& reference, const ValueType& value, const std::string& msg);
+    static void assert_equal(const RefType& reference, const ValueType& value, const std::string& msg);
     template<typename RefType, typename ValueType>
-    void assert_not_equal(const RefType& reference, const ValueType& value, const std::string& msg);
+    static void assert_not_equal(const RefType& reference, const ValueType& value, const std::string& msg);
 
     template <typename RefType, typename ValueType>
-    void fail(const RefType& reference, const ValueType& value, const std::string& msg);
+    static void fail(const RefType& reference, const ValueType& value, const std::string& msg);
 };
 
 class fail_exception : public std::exception