* 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
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    pendingStringTableLength += str.length + 1;
    return stringID;
  }
  function recordMount(fiber: Fiber, parentFiber: Fiber | null) {
    const isRoot = fiber.tag === HostRoot;
    const id = getFiberID(getPrimaryFiber(fiber));
    const hasOwnerMetadata = fiber.hasOwnProperty('_debugOwner');
    const isProfilingSupported = fiber.hasOwnProperty('treeBaseDuration');
    if (isRoot) {
      pushOperation(TREE_OPERATION_ADD);
      pushOperation(id);
      pushOperation(ElementTypeRoot);
      pushOperation(isProfilingSupported ? 1 : 0);
      pushOperation(hasOwnerMetadata ? 1 : 0);
      if (isProfiling) {
        if (displayNamesByRootID !== null) {
          displayNamesByRootID.set(id, getDisplayNameForRoot(fiber));
        }
      }
    } else {
      const {key} = fiber;
      const displayName = getDisplayNameForFiber(fiber);
      const elementType = getElementTypeForFiber(fiber);
      const {_debugOwner} = fiber;
      const ownerID =
        _debugOwner != null ? getFiberID(getPrimaryFiber(_debugOwner)) : 0;
      const parentID = parentFiber