feat(dateparser): use 68 as the yy format pivot year

- Use the same pivot year (68) for 2 digit date years as moment.js.
68 becomes 2068, 69 becomes 1969.

Closes #5735

src/dateparser/dateparser.js

@@ -27,7 +27,7 @@ angular.module('ui.bootstrap.dateparser', [])
       {
         key: 'yy',
         regex: '\\d{2}',
-        apply: function(value) { this.year = +value + 2000; },
+        apply: function(value) { value = +value; this.year = value < 69 ? value + 2000 : value + 1900; },
         formatter: function(date) {
           var _date = new Date();
           _date.setFullYear(Math.abs(date.getFullYear()));

src/dateparser/test/dateparser.spec.js

@@ -282,11 +282,16 @@ describe('date parser', function() {
     it('should work correctly for `yy`', function() {
       expectParse('17.11.13', 'dd.MM.yy', new Date(2013, 10, 17, 0));
       expectParse('02-05-11', 'dd-MM-yy', new Date(2011, 4, 2, 0));
-      expectParse('02/05/80', 'MM/dd/yy', new Date(2080, 1, 5, 0));
+      expectParse('02/05/80', 'MM/dd/yy', new Date(1980, 1, 5, 0));
       expectParse('55/02/05', 'yy/MM/dd', new Date(2055, 1, 5, 0));
       expectParse('11-08-13', 'dd-MM-yy', new Date(2013, 7, 11, 0));
     });
 
+    it('should use `68` as the pivot year for `yy`', function() {
+      expectParse('17.11.68', 'dd.MM.yy', new Date(2068, 10, 17, 0));
+      expectParse('17.11.69', 'dd.MM.yy', new Date(1969, 10, 17, 0));
+    });
+
     it('should work correctly for `y`', function() {
       expectParse('17.11.2013', 'dd.MM.y', new Date(2013, 10, 17, 0));
       expectParse('31.12.2013', 'dd.MM.y', new Date(2013, 11, 31, 0));