fix doc for React Native mountComponent (facebook#7313)

Author: finnigantime

src/renderers/dom/shared/ReactDOMComponent.js

@@ -518,7 +518,7 @@ ReactDOMComponent.Mixin = {
    *
    * @internal
    * @param {ReactReconcileTransaction|ReactServerRenderingTransaction} transaction
-   * @param {?ReactDOMComponent} the containing DOM component instance
+   * @param {?ReactDOMComponent} the parent component instance
    * @param {?object} info about the host container
    * @param {object} context
    * @return {string} The computed markup.

src/renderers/native/ReactNativeBaseComponent.js

@@ -171,8 +171,10 @@ ReactNativeBaseComponent.Mixin = {
   },
 
   /**
-   * @param {string} rootID Root ID of this subtree.
-   * @param {Transaction} transaction For creating/updating.
+   * @param {ReactNativeReconcileTransaction} transaction
+   * @param {?ReactNativeBaseComponent} the parent component instance
+   * @param {?object} info about the host container
+   * @param {object} context
    * @return {string} Unique iOS view tag.
    */
   mountComponent: function(transaction, hostParent, hostContainerInfo, context) {