fix(material/table): Sort correctly angular#20140

Sort correctly when column information has string and numeric values

Author: Hugoer

src/material/table/table-data-source.spec.ts

@@ -47,9 +47,9 @@ describe('MatTableDataSource', () => {
     it('should be able to correctly sort an array of string', () => {
       testSortWithValues(['apples', 'bananas', 'cherries', 'lemons', 'strawberries']);
     });
-    
+
     it('should be able to correctly sort an array of strings and numbers', () => {
-      testSortWithValues([3, 'one', 'two', 'four', 'five']);
+      testSortWithValues(['apples', 'bananas', 'cherries', 'lemons', 'strawberries', 3]);
     });
   });
 });