Partially revert type -> elementType

Author: eps1lon

packages/react-dom/src/server/ReactPartialRenderer.js

@@ -403,14 +403,14 @@ function createOpenTagMarkup(
   return ret;
 }
 
-function validateRenderResult(child, elementType) {
+function validateRenderResult(child, type) {
   if (child === undefined) {
     invariant(
       false,
       '%s(...): Nothing was returned from render. This usually means a ' +
         'return statement is missing. Or, to render nothing, ' +
         'return null.',
-      getComponentName(elementType) || 'Component',
+      getComponentName(type) || 'Component',
     );
   }
 }

packages/react-reconciler/src/ReactChildFiber.js

@@ -118,7 +118,8 @@ function coerceRef(
       // TODO: Clean this up once we turn on the string ref warning for
       // everyone, because the strict mode case will no longer be relevant
       if (returnFiber.mode & StrictMode || warnAboutStringRefs) {
-        const componentName = getComponentName(returnFiber.elementType) || 'Component';
+        const componentName =
+          getComponentName(returnFiber.elementType) || 'Component';
         if (!didWarnAboutStringRefs[componentName]) {
           if (warnAboutStringRefs) {
             warningWithoutStack(