feat(FormGroup): create input from prop

Adds ability to create Form.Group containing a Form.Input from the new
prop

Author: jonthomp

src/components/Form/FormGroup.react.js

@@ -3,21 +3,27 @@
 import * as React from "react";
 import cn from "classnames";
 import FormLabel from "./FormLabel.react";
+import FormInput from "./FormInput.react";
+import type { Props as InputProps } from "./FormInput.react";
 
 type Props = {|
   +children?: React.Node,
   +className?: string,
   +label?: React.Node,
   +isRequired?: boolean,
+  +inputProps?: InputProps,
 |};
 
 function FormGroup({
   className,
   children,
   label,
   isRequired,
+  inputProps,
 }: Props): React.Node {
   const classes = cn("form-group", className);
+  const inputComponent =
+    inputProps && React.createElement(FormInput, inputProps);
   return (
     <div className={classes}>
       {!label ? null : typeof label === "string" ? (
@@ -28,7 +34,7 @@ function FormGroup({
       ) : (
         label
       )}
-      {children}
+      {inputComponent || children}
     </div>
   );
 }