[fix] TextInput focus/blur management

1. Focusing/blurring a TextInput should update TextInputState.
2. Using the focus/blur instance methods should trigger related events.

Close #715

src/components/TextInput/TextInputState.js

@@ -40,9 +40,11 @@ const TextInputState = {
    * noop if the text field was already focused
    */
   focusTextInput(textFieldNode: ?Object) {
-    if (document.activeElement !== textFieldNode && textFieldNode !== null) {
+    if (textFieldNode !== null) {
       this._currentlyFocusedNode = textFieldNode;
-      UIManager.focus(textFieldNode);
+      if (document.activeElement !== textFieldNode) {
+        UIManager.focus(textFieldNode);
+      }
     }
   },
 
@@ -52,9 +54,11 @@ const TextInputState = {
    * noop if it wasn't focused
    */
   blurTextInput(textFieldNode: ?Object) {
-    if (document.activeElement === textFieldNode && textFieldNode !== null) {
+    if (textFieldNode !== null) {
       this._currentlyFocusedNode = null;
-      UIManager.blur(textFieldNode);
+      if (document.activeElement === textFieldNode) {
+        UIManager.blur(textFieldNode);
+      }
     }
   }
 };

src/components/TextInput/index.js

@@ -150,18 +150,12 @@ class TextInput extends Component {
 
   static State = TextInputState;
 
-  blur() {
-    TextInputState.blurTextInput(this._node);
-  }
+  blur: Function;
 
   clear() {
     this._node.value = '';
   }
 
-  focus() {
-    TextInputState.focusTextInput(this._node);
-  }
-
   isFocused() {
     return TextInputState.currentlyFocusedField() === this._node;
   }
@@ -270,6 +264,7 @@ class TextInput extends Component {
 
   _handleBlur = e => {
     const { onBlur } = this.props;
+    TextInputState.blurTextInput(this._node);
     if (onBlur) {
       onBlur(e);
     }
@@ -289,6 +284,7 @@ class TextInput extends Component {
   _handleFocus = e => {
     const { clearTextOnFocus, onFocus, selectTextOnFocus } = this.props;
     const node = this._node;
+    TextInputState.focusTextInput(this._node);
     if (onFocus) {
       onFocus(e);
     }