DevTools does not handle Symbol values logged to cosole.warn/console.error

[leidegre]

React version: DevTools version 4.12.2-d14b6a4bdd

Steps To Reproduce

1. Use console.warn from within a React component where the last argument is typeof "symbol"

Link to code example: https://codesandbox.io/s/pedantic-neumann-711ph?file=/src/App.js

The bug only happens when you make a change, so if you use the code sandbox link you need, open a new window, active dev tools, open the React dev tools and then uncomment line 5: // return null only then will the error actually happen.

I've located the culprit to this line of code

react/packages/react-devtools-shared/src/backend/console.js

Lines 146 to 147 in 0e100ed

	const alreadyHasComponentStack =
	lastArg !== null && isStringComponentStack(lastArg);

And would offer the following change

const alreadyHasComponentStack = typeof lastArg === "string" && isStringComponentStack(lastArg);

The current behavior

React DevTools is implicitly converting a Symbol to a string.

The expected behavior

React DevTools does not implicitly try to convert a Symbol to a string.

[eps1lon]

Thanks for the report.

Also reproduced with DevTools version 4.12.3-8f202a7c8d in Chrome 90

In addition to fixing the bug, it would also be nice to guard against devtools failing so that the UI is unaffected if devtools is faulty.
/cc @bvaughn

[leidegre]

@bvaughn Your the best, thanks for a quick turn around!