* Don't show "context" for classes without either contextType or contextTypes
* For classes with contextTypes, change the label to "legacy context" instead

---
Originally reported by @gaearon via https://github.com/bvaughn/react-devtools-experimental/issues/368
while (child) {
            if (child === a) {
              didFindChild = true;
              a = parentB;
              b = parentA;
              break;
            }
            if (child === b) {
              didFindChild = true;
              b = parentB;
              a = parentA;
              break;
            }
            child = child.sibling;
          }
          if (!didFindChild) {
            throw Error(
              'Child was not found in either parent set. This indicates a bug ' +
                'in React related to the return pointer. Please file an issue.',
            );
          }
        }
      }
      if (a.alternate !== b) {
        throw Error(
          "Return fibers should always be each others' alternates. " +
            'This error is likely caused by a bug in React. Please file an issue.',
        );
      }
    }