Submit the text on Accessory Done button clicked.

Summary:
At the moment we are having a bug that whenever we hit a "Done" button in an input field, a value is not submitted back, so the users cannot complete their work. Here is an example:

https://pxl.cl/28xFq

To fix it, we call a textInputShouldSubmitOnReturn method on Accessory button click.

Changelog
[IOS][Fixed] - Fix keyboard accessory button not triggering onSubmitEditing

Reviewed By: dmitryrykun

Differential Revision: D38152974

fbshipit-source-id: fc026dffd641966cd3d342d95a56c43c71008036

Libraries/Text/TextInput/RCTBaseTextInputView.m

@@ -646,6 +646,8 @@ - (void)reloadInputViewsIfNecessary
 
 - (void)handleInputAccessoryDoneButton
 {
+  // Ignore the value of whether we submitted; just make sure the submit event is called if necessary.
+  [self textInputShouldSubmitOnReturn];
   if ([self textInputShouldReturn]) {
     [self.backedTextInputView endEditing:YES];
   }