feat(jqLite): implement the detach method

Closes angular#5461

Author: jbruni

src/jqLite.js

@@ -46,6 +46,7 @@
  * - [`contents()`](http://api.jquery.com/contents/)
  * - [`css()`](http://api.jquery.com/css/)
  * - [`data()`](http://api.jquery.com/data/)
+ * - [`detach()`](http://api.jquery.com/detach/)
  * - [`empty()`](http://api.jquery.com/empty/)
  * - [`eq()`](http://api.jquery.com/eq/)
  * - [`find()`](http://api.jquery.com/find/) - Limited to lookups by tag name
@@ -437,6 +438,12 @@ function jqLiteEmpty(element) {
   }
 }
 
+function jqLiteRemove(element, keepData) {
+  if (!keepData) jqLiteDealoc(element);
+  var parent = element.parentNode;
+  if (parent) parent.removeChild(element);
+}
+
 //////////////////////////////////////////
 // Functions which are declared directly.
 //////////////////////////////////////////
@@ -536,7 +543,7 @@ forEach({
     return jqLiteInheritedData(element, '$injector');
   },
 
-  removeAttr: function(element,name) {
+  removeAttr: function(element, name) {
     element.removeAttribute(name);
   },
 
@@ -890,10 +897,10 @@ forEach({
     wrapNode.appendChild(element);
   },
 
-  remove: function(element) {
-    jqLiteDealoc(element);
-    var parent = element.parentNode;
-    if (parent) parent.removeChild(element);
+  remove: jqLiteRemove,
+
+  detach: function(element) {
+    jqLiteRemove(element, true);
   },
 
   after: function(element, newElement) {

test/jqLiteSpec.js

@@ -460,6 +460,20 @@ describe('jqLite', function() {
     }));
 
 
+    it('should keep data if an element is removed via detach()', function() {
+      var root = jqLite('<div><span>abc</span></div>'),
+          span = root.find('span'),
+          data = span.data();
+
+      span.data('foo', 'bar');
+      span.detach();
+
+      expect(data).toEqual({foo: 'bar'});
+
+      span.remove();
+    });
+
+
     it('should retrieve all data if called without params', function() {
       var element = jqLite(a);
       expect(element.data()).toEqual({});
@@ -1586,6 +1600,16 @@ describe('jqLite', function() {
   });
 
 
+  describe('detach', function() {
+    it('should detach', function() {
+      var root = jqLite('<div><span>abc</span></div>');
+      var span = root.find('span');
+      expect(span.detach()).toEqual(span);
+      expect(root.html()).toEqual('');
+    });
+  });
+
+
   describe('after', function() {
     it('should after', function() {
       var root = jqLite('<div><span></span></div>');