Pass context to DOM wrappers, use it in <option>

src/renderers/dom/client/wrappers/ReactDOMOption.js

@@ -16,7 +16,6 @@ var ReactChildren = require('ReactChildren');
 var ReactClass = require('ReactClass');
 var ReactDOMSelect = require('ReactDOMSelect');
 var ReactElement = require('ReactElement');
-var ReactInstanceMap = require('ReactInstanceMap');
 var ReactPropTypes = require('ReactPropTypes');
 
 var assign = require('Object.assign');
@@ -56,7 +55,7 @@ var ReactDOMOption = ReactClass.createClass({
     }
 
     // Look up whether this option is 'selected' via parent-based context
-    var context = ReactInstanceMap.get(this)._context;
+    var context = this.context;
     var selectValue = context[valueContextKey];
 
     // If context key is null (e.g., no specified value or after initial mount)

src/renderers/shared/reconciler/ReactCompositeComponent.js

@@ -326,12 +326,10 @@ var ReactCompositeComponentMixin = {
    */
   _maskContext: function(context) {
     var maskedContext = null;
-    // This really should be getting the component class for the element,
-    // but we know that we're not going to need it for built-ins.
-    if (typeof this._currentElement.type === 'string') {
-      return emptyObject;
-    }
-    var contextTypes = this._currentElement.type.contextTypes;
+    var Component = ReactNativeComponent.getComponentClassForElement(
+      this._currentElement
+    );
+    var contextTypes = Component.contextTypes;
     if (!contextTypes) {
       return emptyObject;
     }