TextInput: Default blurOnSubmit in JS

Summary:
Consolidates the logic for the default value of `blurOnSubmit` on `TextInput` in the JavaScript component.

This only materially impacts Fabric.

Changelog:
[Internal]

Reviewed By: mdvacca

Differential Revision: D21491482

fbshipit-source-id: 16d8aba32e7d0321a4583e87e03405ea587e35d4

Libraries/Components/TextInput/TextInput.js

@@ -1057,6 +1057,10 @@ function InternalTextInput(props: Props): React.Node {
     // This is a hack to let Flow know we want an exact object
   |} = {...null};
 
+  // The default value for `blurOnSubmit` is true for single-line fields and
+  // false for multi-line fields.
+  const blurOnSubmit = props.blurOnSubmit ?? !props.multiline;
+
   if (Platform.OS === 'ios') {
     const RCTTextInputView = props.multiline
       ? RCTMultilineTextInputView
@@ -1073,6 +1077,7 @@ function InternalTextInput(props: Props): React.Node {
       <RCTTextInputView
         ref={_setNativeRef}
         {...props}
+        blurOnSubmit={blurOnSubmit}
         dataDetectorTypes={props.dataDetectorTypes}
         mostRecentEventCount={mostRecentEventCount}
         onBlur={_onBlur}
@@ -1108,6 +1113,7 @@ function InternalTextInput(props: Props): React.Node {
         ref={_setNativeRef}
         {...props}
         autoCapitalize={autoCapitalize}
+        blurOnSubmit={blurOnSubmit}
         children={children}
         disableFullscreenUI={props.disableFullscreenUI}
         mostRecentEventCount={mostRecentEventCount}

Libraries/Components/TextInput/__tests__/__snapshots__/TextInput-test.js.snap

@@ -4,6 +4,7 @@ exports[`TextInput tests should render as expected: should deep render when mock
 <RCTSinglelineTextInputView
   accessible={true}
   allowFontScaling={true}
+  blurOnSubmit={true}
   focusable={true}
   forwardedRef={null}
   mostRecentEventCount={0}
@@ -31,6 +32,7 @@ exports[`TextInput tests should render as expected: should deep render when not
 <RCTSinglelineTextInputView
   accessible={true}
   allowFontScaling={true}
+  blurOnSubmit={true}
   focusable={true}
   forwardedRef={null}
   mostRecentEventCount={0}