Describe what you were doing when the bug occurred:
1. Clicking back to go back through the frames following a profile session. I think I got to zero and then clicked it again and then it errored

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DevTools version: 4.8.2-fed4ae024

Call stack: at getCommitTree (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:17661:26)
    at getCommitTree (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:17710:30)
    at getCommitTree (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:17710:30)
    at getCommitTree (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:17710:30)
    at getCommitTree (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:17710:30)
    at getCommitTree (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:17710:30)
    at getCommitTree (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:17710:30)
    at getCommitTree (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:17710:30)
    at getCommitTree (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:17710:30)
    at getCommitTree (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:17710:30)

Component stack: at CommitRankedAutoSizer (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:31963:48)
    at div
    at div
    at div
    at SettingsModalContextController (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:26139:23)
    at Profiler_Profiler (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:33363:48)
    at ErrorBoundary (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:27172:5)
    at PortaledContent (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:27303:32)
    at div
    at div
    at ProfilerContextController (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:30463:23)
    at TreeContextController (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:22538:23)
    at SettingsContextController (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:23040:27)
    at ModalDialogContextController (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:28328:23)
    at DevTools_DevTools (chrome-extension://fmkadmapgofadopljbjfkapdkoienihi/build/main.js:33797:21)
/**
 * Copyright (c) Facebook, Inc. and its affiliates.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 *
 * @flow
 */
import {
  __DEBUG__,
  TREE_OPERATION_ADD,
  TREE_OPERATION_REMOVE,
  TREE_OPERATION_REMOVE_ROOT,
  TREE_OPERATION_REORDER_CHILDREN,
  TREE_OPERATION_UPDATE_TREE_BASE_DURATION,
  TREE_OPERATION_UPDATE_ERRORS_OR_WARNINGS,
} from 'react-devtools-shared/src/constants';
import {utfDecodeString} from 'react-devtools-shared/src/utils';
import {ElementTypeRoot} from 'react-devtools-shared/src/types';
import ProfilerStore from 'react-devtools-shared/src/devtools/ProfilerStore';
import type {ElementType} from 'react-devtools-shared/src/types';
import type {
  CommitTree,
  CommitTreeNode,
  ProfilingDataForRootFrontend,
} from 'react-devtools-shared/src/devtools/views/Profiler/types';