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

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Originally reported by @gaearon via https://github.com/bvaughn/react-devtools-experimental/issues/368
function getElementTypeForFiber(fiber: Fiber): ElementType {
    const {type, tag} = fiber;
    switch (tag) {
      case ClassComponent:
      case IncompleteClassComponent:
        return ElementTypeClass;
      case FunctionComponent:
      case IndeterminateComponent:
        return ElementTypeFunction;
      case ForwardRef:
        return ElementTypeForwardRef;
      case HostRoot:
        return ElementTypeRoot;
      case HostComponent:
        return ElementTypeHostComponent;
      case HostPortal:
      case HostText:
      case Fragment:
        return ElementTypeOtherOrUnknown;
      case MemoComponent:
      case SimpleMemoComponent:
        return ElementTypeMemo;
      default:
        const typeSymbol = getTypeSymbol(type);
        switch (typeSymbol) {
          case CONCURRENT_MODE_NUMBER:
          case CONCURRENT_MODE_SYMBOL_STRING:
          case DEPRECATED_ASYNC_MODE_SYMBOL_STRING:
            return ElementTypeOtherOrUnknown;
          case CONTEXT_PROVIDER_NUMBER: