fix(chips): fix chips focus functionality

- The normal mobile devices won't trigger the focus on the element.
Focusing the element on `ng-click` fixes that issue.
Through keeping and redirecting to `ng-focus` it's still possible to select chips through keyboard
- At the moment, we only reset the selectedChip variable but we don't
  apply that to the view, so we need to run an async evaluation.

Fixes #5897. Fixes #5662. Closes #5941

# Conflicts:
#	src/components/chips/chips.spec.js

Author: devversion

src/components/chips/chips.spec.js

@@ -14,6 +14,8 @@ describe('<md-chips>', function() {
     '<md-chips ng-model="items" md-on-remove="removeChip($chip, $index)"></md-chips>';
   var CHIP_SELECT_TEMPLATE =
     '<md-chips ng-model="items" md-on-select="selectChip($chip)"></md-chips>';
+  var CHIP_READONLY_TEMPLATE =
+    '<md-chips ng-model="items" readonly="isReadonly"></md-chips>';
   var CHIP_READONLY_AUTOCOMPLETE_TEMPLATE =
     '<md-chips ng-model="items" readonly="true">' +
     '  <md-autocomplete md-items="item in [\'hi\', \'ho\', \'he\']"></md-autocomplete>' +
@@ -254,12 +256,53 @@ describe('<md-chips>', function() {
         expect(scope.items[3].uppername).toBe('GRAPE');
       });
 
-      it('should not throw an error when using readonly with an autocomplete', function() {
-        var element = buildChips(CHIP_READONLY_AUTOCOMPLETE_TEMPLATE);
+      describe('when readonly', function() {
+        var element, ctrl;
 
-        $timeout.flush();
+        it("properly toggles the controller's readonly property", function() {
+          element = buildChips(CHIP_READONLY_TEMPLATE);
+          ctrl = element.controller('mdChips');
+
+          expect(ctrl.readonly).toBeFalsy();
+
+          scope.$apply('isReadonly = true');
+
+          expect(ctrl.readonly).toBeTruthy();
+        });
+
+        it("properly toggles the wrapper's .md-readonly class", function() {
+          element = buildChips(CHIP_READONLY_TEMPLATE);
+          ctrl = element.controller('mdChips');
+
+          expect(element.find('md-chips-wrap')).not.toHaveClass('md-readonly');
+
+          scope.$apply('isReadonly = true');
+
+          expect(element.find('md-chips-wrap')).toHaveClass('md-readonly');
+        });
+
+        it('is false with empty items should not hide the chips wrapper', function() {
+          scope.isReadonly = false;
+          scope.items = [];
+          element = buildChips(CHIP_READONLY_TEMPLATE);
+
+          expect(element.find('md-chips-wrap').length).toBe(1);
+        });
+
+        it('is true with empty items should not hide the chips wrapper', function() {
+          scope.isReadonly = true;
+          scope.items = [];
+          element = buildChips(CHIP_READONLY_TEMPLATE);
+
+          expect(element.find('md-chips-wrap').length).toBe(1);
+        });
+
+        it('is true should not throw an error when used with an autocomplete', function() {
+          element = buildChips(CHIP_READONLY_AUTOCOMPLETE_TEMPLATE);
+          $timeout.flush();
 
-        expect($exceptionHandler.errors).toEqual([]);
+          expect($exceptionHandler.errors).toEqual([]);
+        });
       });
 
       it('should disallow duplicate object chips', function() {
@@ -451,6 +494,123 @@ describe('<md-chips>', function() {
         }));
       });
 
+      describe('md-max-chips', function() {
+
+        beforeEach(function() {
+          // Clear default items to test the max chips functionality
+          scope.items = [];
+        });
+
+        it('should not add a new chip if the max-chips limit is reached', function () {
+          var element = buildChips('<md-chips ng-model="items" md-max-chips="1"></md-chips>');
+          var ctrl = element.controller('mdChips');
+
+          element.scope().$apply(function() {
+            ctrl.chipBuffer = 'Test';
+            simulateInputEnterKey(ctrl);
+          });
+
+          expect(scope.items.length).toBe(1);
+
+          element.scope().$apply(function() {
+            ctrl.chipBuffer = 'Test 2';
+            simulateInputEnterKey(ctrl);
+          });
+
+          expect(scope.items.length).not.toBe(2);
+        });
+
+        it('should update the md-max-chips model validator for forms', function() {
+          var template =
+            '<form name="form">' +
+            '<md-chips name="chips" ng-model="items" md-max-chips="1"></md-chips>' +
+            '</form>';
+
+          var element = buildChips(template);
+          var ctrl = element.find('md-chips').controller('mdChips');
+
+          element.scope().$apply(function() {
+            ctrl.chipBuffer = 'Test';
+            simulateInputEnterKey(ctrl);
+          });
+
+          expect(scope.form.chips.$error['md-max-chips']).toBe(true);
+        });
+
+        it('should not reset the buffer if the maximum is reached', function() {
+          var element = buildChips('<md-chips ng-model="items" md-max-chips="1"></md-chips>');
+          var ctrl = element.controller('mdChips');
+
+          element.scope().$apply(function() {
+            ctrl.chipBuffer = 'Test';
+            simulateInputEnterKey(ctrl);
+          });
+
+          expect(scope.items.length).toBe(1);
+
+          element.scope().$apply(function() {
+            ctrl.chipBuffer = 'Test 2';
+            simulateInputEnterKey(ctrl);
+          });
+
+          expect(ctrl.chipBuffer).toBe('Test 2');
+          expect(scope.items.length).not.toBe(2);
+        });
+      });
+
+      describe('focus functionality', function() {
+        var element, ctrl;
+
+        beforeEach(function() {
+          element = buildChips(CHIP_SELECT_TEMPLATE);
+          ctrl = element.controller('mdChips');
+          document.body.appendChild(element[0]);
+        });
+
+        afterEach(function() {
+          element.remove();
+          element = ctrl = null;
+        });
+
+        it('should focus the chip when clicking / touching on the chip', function() {
+          ctrl.focusChip = jasmine.createSpy('focusChipSpy');
+
+          var chips = getChipElements(element);
+          expect(chips.length).toBe(3);
+
+          chips.children().eq(0).triggerHandler('click');
+
+          expect(ctrl.focusChip).toHaveBeenCalledTimes(1);
+        });
+
+        it('should focus the chip through normal content focus', function() {
+          scope.selectChip = jasmine.createSpy('focusChipSpy');
+          var chips = getChipElements(element);
+          expect(chips.length).toBe(3);
+
+          chips.children().eq(0).triggerHandler('focus');
+
+          expect(scope.selectChip).toHaveBeenCalledTimes(1);
+        });
+
+        it('should blur the chip correctly', function() {
+          var chips = getChipElements(element);
+          expect(chips.length).toBe(3);
+
+          var chipContent = chips.children().eq(0);
+          chipContent.triggerHandler('focus');
+
+          expect(ctrl.selectedChip).toBe(0);
+
+          chipContent.eq(0).triggerHandler('blur');
+
+          scope.$digest();
+
+          expect(ctrl.selectedChip).toBe(-1);
+        });
+
+      });
+
       describe('md-autocomplete', function() {
         var AUTOCOMPLETE_CHIPS_TEMPLATE = '\
           <md-chips ng-model="items">\

src/components/chips/js/chipDirective.js

@@ -52,7 +52,8 @@ function MdChip($mdTheming, $mdUtil) {
 
       if (ctrl) angular.element(element[0].querySelector('.md-chip-content'))
           .on('blur', function () {
-            ctrl.selectedChip = -1;
+            ctrl.resetSelectedChip();
+            ctrl.$scope.$applyAsync();
           });
     };
   }

src/components/chips/js/chipsDirective.js

@@ -109,6 +109,7 @@
           <div class="md-chip-content"\
               tabindex="-1"\
               aria-hidden="true"\
+              ng-click="!$mdChipsCtrl.readonly && $mdChipsCtrl.focusChip($index)"\
               ng-focus="!$mdChipsCtrl.readonly && $mdChipsCtrl.selectChip($index)"\
               md-chip-transclude="$mdChipsCtrl.chipContentsTemplate"></div>\
           <div ng-if="!$mdChipsCtrl.readonly"\