fix(ionRadio): fix adjacent selectors that break in iOS9

Closes #4347

Author: mhartington

Diff for: js/angular/directive/radio.js

@@ -35,8 +35,10 @@ IonicModule
     template:
       '<label class="item item-radio">' +
         '<input type="radio" name="radio-group">' +
-        '<div class="item-content disable-pointer-events" ng-transclude></div>' +
-        '<i class="radio-icon disable-pointer-events icon ion-checkmark"></i>' +
+        '<div class="radio-content">'+
+          '<div class="item-content disable-pointer-events" ng-transclude></div>' +
+          '<i class="radio-icon disable-pointer-events icon ion-checkmark"></i>' +
+        '</div>'+
       '</label>',
 
     compile: function(element, attr) {

Diff for: scss/_radio.scss

@@ -34,24 +34,14 @@
   position: absolute;
   left: -9999px;
 
-  &:checked ~ .item-content {
+  &:checked + .radio-content .item-content {
     /* style the item content when its checked */
     background: #f7f7f7;
   }
 
-  &:checked ~ .radio-icon {
+  &:checked + .radio-content .radio-icon {
     /* show the checkmark icon when its checked */
     visibility: visible;
   }
 }
 
-// Hack for Android to correctly display the checked item
-// http://timpietrusky.com/advanced-checkbox-hack
-.platform-android.grade-b .item-radio,
-.platform-android.grade-c .item-radio {
-  -webkit-animation: androidCheckedbugfix infinite 1s;
-}
-@-webkit-keyframes androidCheckedbugfix {
-  from { padding: 0; }
-  to { padding: 0; }
-}