Add debounce (formerly known as job), tests, docs.

test/unit/utils.html

@@ -36,10 +36,6 @@ subject to an additional IP rights grant found at http://polymer.github.io/PATEN
 
   suite('CSS utilities', function() {
 
-    test('$$:', function() {
-      // TODO
-    });
-
     test('toggleClass', function() {
 
       window.el1.toggleClass('foo-class', true);
@@ -59,6 +55,48 @@ subject to an additional IP rights grant found at http://polymer.github.io/PATEN
 
   });
 
+  suite('debounce', function() {
+
+    test('debounce (no-wait)', function(done) {
+
+      var called = 0;
+      var cb = function() {
+        called++;
+      };
+
+      window.el1.debounce('foo', cb);
+      window.el1.debounce('foo', cb);
+      window.el1.debounce('foo', cb);
+
+      setTimeout(function() {
+        assert.equal(called, 1, 'debounce should be called exactly once');
+        done();
+      }, 50);
+
+    });
+
+    test('debounce (wait)', function(done) {
+
+      var called = 0;
+      var now = Date.now();
+      var cb = function() {
+        called++;
+      };
+
+      window.el1.debounce('foo', cb);
+      window.el1.debounce('foo', cb, 100);
+      window.el1.debounce('foo', cb, 100);
+
+      setTimeout(function() {
+        assert.equal(called, 1, 'debounce should be called exactly once');
+        assert(Date.now() - now > 100, 'debounce should be called after at least 100ms');
+        done();
+      }, 200);
+
+    });
+
+  });
+
 </script>
 </body>
 </html>