* 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
displayNamesByRootID = new Map();
    initialTreeBaseDurationsMap = new Map(idToTreeBaseDurationMap);
    initialIDToRootMap = new Map(idToRootMap);
    idToContextsMap = new Map();
    hook.getFiberRoots(rendererID).forEach(root => {
      const rootID = getFiberID(getPrimaryFiber(root.current));
      ((displayNamesByRootID: any): DisplayNamesByRootID).set(
        rootID,
        getDisplayNameForRoot(root.current),
      );
      if (shouldRecordChangeDescriptions) {
         R
         F
         s
        crawlToInitializeContextsMap(root.current);
      }
    });
    isProfiling = true;
    profilingStartTime = getCurrentTime();
    rootToCommitProfilingMetadataMap = new Map();
  }
  function stopProfiling() {
    isProfiling = false;
    recordChangeDescriptions = false;
  }
   Automatically start profiling so that we don't miss timing info from initial "mount".
  if (
    sessionStorageGetItem(SESSION_STORAGE_RELOAD_AND_PROFILE_KEY) === 'true'
  ) {
    startProfiling(