Generalization of isInAParentText context

Summary:
Currently `isInAParentText` context works as imaginary `isInAAncestorText` context (not like a real `isInAParentText`).
Let's imagine we have hierarchy like:
`View -> Text -> Text* -> View* -> Text* -> Text* -> View*`
With current implementation all nodes marked with asterisk have `isInAParentText` context, which is incorrect (because some of them actually in View context).

With the new implemetations it will work like this:
`View -> Text -> Text* -> View* -> Text -> Text* -> View*`
So, only nodes which have <Text> (or <TextInput>) as a parent will have `isInAParentText` context.

This change allows to select proper `Text` vs. `VirtualText` component in cases where <Text> and <View> components can interleave each other.

Reviewed By: sahrens

Differential Revision: D6690495

fbshipit-source-id: f7c59b23d0eaf68a1d08036b858d99c9547f7878

Libraries/Components/View/View.js

@@ -14,17 +14,18 @@
 
 const NativeMethodsMixin = require('NativeMethodsMixin');
 const Platform = require('Platform');
-const PropTypes = require('prop-types');
 const React = require('React');
 const ReactNativeStyleAttributes = require('ReactNativeStyleAttributes');
 const ReactNativeViewAttributes = require('ReactNativeViewAttributes');
 const ViewPropTypes = require('ViewPropTypes');
+const {ViewContextTypes} = require('ViewContext');
 
 const createReactClass = require('create-react-class');
 const invariant = require('fbjs/lib/invariant');
 const requireNativeComponent = require('requireNativeComponent');
 
 import type {ViewProps} from 'ViewPropTypes';
+import type {ViewChildContext} from 'ViewContext';
 
 export type Props = ViewProps;
 
@@ -56,8 +57,12 @@ const View = createReactClass({
     validAttributes: ReactNativeViewAttributes.RCTView,
   },
 
-  contextTypes: {
-    isInAParentText: PropTypes.bool,
+  childContextTypes: ViewContextTypes,
+
+  getChildContext(): ViewChildContext {
+    return {
+      isInAParentText: false,
+    };
   },
 
   render() {

Libraries/Components/View/ViewContext.js

@@ -0,0 +1,23 @@
+/**
+ * Copyright (c) 2015-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ *
+ * @providesModule ViewContext
+ * @flow
+ * @format
+ */
+'use strict';
+
+const PropTypes = require('prop-types');
+
+export type ViewChildContext = {|
+  +isInAParentText: boolean,
+|};
+
+export const ViewContextTypes = {
+  isInAParentText: PropTypes.bool,
+};