refactor(booleanAttrs, ngSwitch): use link function instead of compile function where appropriate

Replace two compile functions that immediately return a post-link function with link function definitions instead.

Closes #5664

Author: Gias Kay Lee

src/ng/directive/booleanAttrs.js

@@ -336,12 +336,10 @@ forEach(BOOLEAN_ATTR, function(propName, attrName) {
   ngAttributeAliasDirectives[normalized] = function() {
     return {
       priority: 100,
-      compile: function() {
-        return function(scope, element, attr) {
-          scope.$watch(attr[normalized], function ngBooleanAttrWatchAction(value) {
-            attr.$set(attrName, !!value);
-          });
-        };
+      link: function(scope, element, attr) {
+        scope.$watch(attr[normalized], function ngBooleanAttrWatchAction(value) {
+          attr.$set(attrName, !!value);
+        });
       }
     };
   };

src/ng/directive/ngSwitch.js

@@ -168,11 +168,9 @@ var ngSwitchWhenDirective = ngDirective({
   transclude: 'element',
   priority: 800,
   require: '^ngSwitch',
-  compile: function(element, attrs) {
-    return function(scope, element, attr, ctrl, $transclude) {
-      ctrl.cases['!' + attrs.ngSwitchWhen] = (ctrl.cases['!' + attrs.ngSwitchWhen] || []);
-      ctrl.cases['!' + attrs.ngSwitchWhen].push({ transclude: $transclude, element: element });
-    };
+  link: function(scope, element, attrs, ctrl, $transclude) {
+    ctrl.cases['!' + attrs.ngSwitchWhen] = (ctrl.cases['!' + attrs.ngSwitchWhen] || []);
+    ctrl.cases['!' + attrs.ngSwitchWhen].push({ transclude: $transclude, element: element });
   }
 });