**Do you want to request a *feature* or report a *bug*?**

Feature

**What is the current behavior?**

While server rendering React DOM and then hydrating with a different structure, React rightly warns that there are inconsistencies. But when I first saw these warnings I was not sure exactly what was going wrong.

Here are a few of the warnings I have been receiving:

```
Warning: Did not find a matching <button> in <div>.

Warning: Did not find a matching <img> in <div>.

Warning: Did not expect server HTML to contain a <div> in <div>.
```

Only on that last error did I catch on that this was a problem with server-rendering and the inconsistencies between that and my client render (intentional at the moment while testing some things in unpure render functions).

**What is the expected behavior?**

Being more explicit that this was a rendering inconsistency between server and client.

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

React v16-beta.1
if (nextProp) {
          
          ensureListeningTo(rootContainerElement, propKey);
        }
        if (!updatePayload && lastProp !== nextProp) {
          
          
          
          updatePayload = [];
        }
      } else {
        
        
        (updatePayload = updatePayload || []).push(propKey, nextProp);
      }
    }
    if (styleUpdates) {
      (updatePayload = updatePayload || []).push(STYLE, styleUpdates);
    }
    return updatePayload;
  },
  
  updateProperties(
    domElement: Element,
    updatePayload: Array<any>,
    tag: string,
    lastRawProps: Object,
    nextRawProps: Object,
  ): void {
    var wasCustomComponentTag = isCustomComponent(tag, lastRawProps);