iss is unordered_multimap, so can't rely on order

Change-Id: Ief399439bdde047dfbaef43f2262e6212db8bd7e

svl/qa/unit/items/test_IndexedStyleSheets.cxx

@@ -133,6 +133,7 @@ void IndexedStyleSheetsTest::StyleSheetsCanBeRetrievedByTheirName()
     std::vector<unsigned> r = iss.FindPositionsByName(name1);
     CPPUNIT_ASSERT_EQUAL_MESSAGE("Two style sheets are found by 'name1'",
             2u, static_cast<unsigned>(r.size()));
+    std::sort (r.begin(), r.end());
     CPPUNIT_ASSERT_EQUAL(0u, r.at(0));
     CPPUNIT_ASSERT_EQUAL(2u, r.at(1));