* 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
const operations = new Array(
       I
      2 +  [
       H
      1 +  [
         T
        pendingStringTableLength +
         A
         [
        (numUnmountIDs > 0 ? 2 + numUnmountIDs : 0) +
         R
        pendingOperations.length,
    );
     I
     T
     W
    let i = 0;
    operations[i++] = rendererID;
    operations[i++] = currentRootID;  U
     N
     [
    operations[i++] = pendingStringTableLength;
    pendingStringTable.forEach((value, key) => {
      operations[i++] = key.length;
      const encodedKey = utfEncodeString(key);
      for (let j = 0; j < encodedKey.length; j++) {
        operations[i + j] = encodedKey[j];
      }
      i += key.length;
    });