Provide component reference in ReactDOMFiberTextarea warnings (#13361)

* Provide component reference if possible in ReactDOMFiberTextarea.js warning

* Nits

Author: raunofreiberg

packages/react-dom/src/__tests__/ReactDOMTextarea-test.js

@@ -399,22 +399,22 @@ describe('ReactDOMTextarea', () => {
   });
 
   it('should warn if value and defaultValue are specified', () => {
+    const InvalidComponent = () => (
+      <textarea value="foo" defaultValue="bar" readOnly={true} />
+    );
     expect(() =>
-      ReactTestUtils.renderIntoDocument(
-        <textarea value="foo" defaultValue="bar" readOnly={true} />,
-      ),
+      ReactTestUtils.renderIntoDocument(<InvalidComponent />),
     ).toWarnDev(
-      'Textarea elements must be either controlled or uncontrolled ' +
+      'InvalidComponent contains a textarea with both value and defaultValue props. ' +
+        'Textarea elements must be either controlled or uncontrolled ' +
         '(specify either the value prop, or the defaultValue prop, but not ' +
         'both). Decide between using a controlled or uncontrolled textarea ' +
         'and remove one of these props. More info: ' +
         'https://fb.me/react-controlled-components',
     );
 
     // No additional warnings are expected
-    ReactTestUtils.renderIntoDocument(
-      <textarea value="foo" defaultValue="bar" readOnly={true} />,
-    );
+    ReactTestUtils.renderIntoDocument(<InvalidComponent />);
   });
 
   it('should not warn about missing onChange in uncontrolled textareas', () => {

packages/react-dom/src/client/ReactDOMFiberTextarea.js

@@ -11,6 +11,7 @@ import invariant from 'shared/invariant';
 import warning from 'shared/warning';
 
 import ReactControlledValuePropTypes from '../shared/ReactControlledValuePropTypes';
+import {getCurrentFiberOwnerNameInDevOrNull} from 'react-reconciler/src/ReactCurrentFiber';
 
 let didWarnValDefaultVal = false;
 
@@ -70,11 +71,13 @@ export function initWrapperState(element: Element, props: Object) {
     ) {
       warning(
         false,
-        'Textarea elements must be either controlled or uncontrolled ' +
+        '%s contains a textarea with both value and defaultValue props. ' +
+          'Textarea elements must be either controlled or uncontrolled ' +
           '(specify either the value prop, or the defaultValue prop, but not ' +
           'both). Decide between using a controlled or uncontrolled textarea ' +
           'and remove one of these props. More info: ' +
           'https://fb.me/react-controlled-components',
+        getCurrentFiberOwnerNameInDevOrNull() || 'A component',
       );
       didWarnValDefaultVal = true;
     }