**Bug**

**What is the current behavior?**

IE11 Windows 10 text area placeholder not rendering initially.
[https://jsfiddle.net/fztx6vqp/](https://jsfiddle.net/fztx6vqp/)

**What is the expected behavior?**

Placeholder should be visible on initial render.

**Which versions of React, and which browser / OS are affected by this issue? Did this work in previous versions of React?**

16.0.0, IE11, Windows 10
Appears to be a regression in 16.0.0 - #6731 

extraAttributeNames.delete(propertyInfo.attributeName);
            serverValue = DOMPropertyOperations.getValueForProperty(
              domElement,
              propKey,
              nextProp,
            );
          } else {
            let ownNamespace = parentNamespace;
            if (ownNamespace === HTML_NAMESPACE) {
              ownNamespace = getIntrinsicNamespace(tag);
            }
            if (ownNamespace === HTML_NAMESPACE) {
              
              extraAttributeNames.delete(propKey.toLowerCase());
            } else {
              
              extraAttributeNames.delete(propKey);
            }
            serverValue = DOMPropertyOperations.getValueForAttribute(
              domElement,
              propKey,
              nextProp,
            );
          }
          if (nextProp !== serverValue) {
            warnForPropDifference(propKey, serverValue, nextProp);