Don't convert error to string

[hanneslund]

Stack trace disappears when error is converted to string.
I changed the types in log.ts to match console.log/console.error/console.warn.

fixes #31591

[ijjk]

Stats from current PR

Default Build (Decrease detected ✓)

General Overall decrease ✓

	vercel/next.js canary	hanneslund/next.js issue-31591	Change
buildDuration	18s	18.4s	⚠️ +381ms
buildDurationCached	7.1s	7.1s	-8ms
nodeModulesSize	475 MB	475 MB	-143 B

Page Load Tests Overall decrease ⚠️

	vercel/next.js canary	hanneslund/next.js issue-31591	Change
/ failed reqs	0	0	✓
/ total time (seconds)	4.483	4.543	⚠️ +0.06
/ avg req/sec	557.6	550.33	⚠️ -7.27
/error-in-render failed reqs	0	0	✓
/error-in-render total time (seconds)	1.564	1.584	⚠️ +0.02
/error-in-render avg req/sec	1598.73	1578.46	⚠️ -20.27

Client Bundles (main, webpack)

	vercel/next.js canary	hanneslund/next.js issue-31591	Change
925.HASH.js gzip	179 B	179 B	✓
framework-HASH.js gzip	42 kB	42 kB	✓
main-HASH.js gzip	28.8 kB	28.8 kB	✓
webpack-HASH.js gzip	1.44 kB	1.44 kB	✓
Overall change	72.5 kB	72.5 kB	✓

Legacy Client Bundles (polyfills)

	vercel/next.js canary	hanneslund/next.js issue-31591	Change
polyfills-HASH.js gzip	31 kB	31 kB	✓
Overall change	31 kB	31 kB	✓

Client Pages

	vercel/next.js canary	hanneslund/next.js issue-31591	Change
_app-HASH.js gzip	1.36 kB	1.36 kB	✓
_error-HASH.js gzip	193 B	193 B	✓
amp-HASH.js gzip	308 B	308 B	✓
css-HASH.js gzip	327 B	327 B	✓
dynamic-HASH.js gzip	2.69 kB	2.69 kB	✓
head-HASH.js gzip	359 B	359 B	✓
hooks-HASH.js gzip	920 B	920 B	✓
image-HASH.js gzip	5.7 kB	5.7 kB	✓
index-HASH.js gzip	263 B	263 B	✓
link-HASH.js gzip	2.64 kB	2.64 kB	✓
routerDirect..HASH.js gzip	320 B	320 B	✓
script-HASH.js gzip	391 B	391 B	✓
withRouter-HASH.js gzip	318 B	318 B	✓
85e02e95b279..7e3.css gzip	107 B	107 B	✓
Overall change	15.9 kB	15.9 kB	✓

Client Build Manifests

	vercel/next.js canary	hanneslund/next.js issue-31591	Change
_buildManifest.js gzip	459 B	459 B	✓
Overall change	459 B	459 B	✓

Rendered Page Sizes

	vercel/next.js canary	hanneslund/next.js issue-31591	Change
index.html gzip	532 B	532 B	✓
link.html gzip	545 B	545 B	✓
withRouter.html gzip	527 B	527 B	✓
Overall change	1.6 kB	1.6 kB	✓

---

Default Build with SWC (Increase detected ⚠️)

General Overall decrease ✓

	vercel/next.js canary	hanneslund/next.js issue-31591	Change
buildDuration	19.9s	19.4s	-502ms
buildDurationCached	7.1s	6.9s	-139ms
nodeModulesSize	475 MB	475 MB	-143 B

Page Load Tests Overall increase ✓

	vercel/next.js canary	hanneslund/next.js issue-31591	Change
/ failed reqs	0	0	✓
/ total time (seconds)	4.548	4.453	-0.09
/ avg req/sec	549.71	561.38	+11.67
/error-in-render failed reqs	0	0	✓
/error-in-render total time (seconds)	1.591	1.453	-0.14
/error-in-render avg req/sec	1571.59	1720.47	+148.88

Client Bundles (main, webpack)

	vercel/next.js canary	hanneslund/next.js issue-31591	Change
925.HASH.js gzip	178 B	178 B	✓
framework-HASH.js gzip	42.2 kB	42.2 kB	✓
main-HASH.js gzip	29.2 kB	29.2 kB	✓
webpack-HASH.js gzip	1.45 kB	1.45 kB	✓
Overall change	73.1 kB	73.1 kB	✓

Legacy Client Bundles (polyfills)

	vercel/next.js canary	hanneslund/next.js issue-31591	Change
polyfills-HASH.js gzip	31 kB	31 kB	✓
Overall change	31 kB	31 kB	✓

Client Pages

	vercel/next.js canary	hanneslund/next.js issue-31591	Change
_app-HASH.js gzip	1.35 kB	1.35 kB	✓
_error-HASH.js gzip	179 B	179 B	✓
amp-HASH.js gzip	312 B	312 B	✓
css-HASH.js gzip	324 B	324 B	✓
dynamic-HASH.js gzip	2.71 kB	2.71 kB	✓
head-HASH.js gzip	357 B	357 B	✓
hooks-HASH.js gzip	921 B	921 B	✓
image-HASH.js gzip	5.79 kB	5.79 kB	✓
index-HASH.js gzip	261 B	261 B	✓
link-HASH.js gzip	2.76 kB	2.76 kB	✓
routerDirect..HASH.js gzip	322 B	322 B	✓
script-HASH.js gzip	392 B	392 B	✓
withRouter-HASH.js gzip	317 B	317 B	✓
85e02e95b279..7e3.css gzip	107 B	107 B	✓
Overall change	16.1 kB	16.1 kB	✓

Client Build Manifests

	vercel/next.js canary	hanneslund/next.js issue-31591	Change
_buildManifest.js gzip	456 B	456 B	✓
Overall change	456 B	456 B	✓

Rendered Page Sizes

	vercel/next.js canary	hanneslund/next.js issue-31591	Change
index.html gzip	530 B	530 B	✓
link.html gzip	544 B	544 B	✓
withRouter.html gzip	527 B	527 B	✓
Overall change	1.6 kB	1.6 kB	✓

Commit: 01e6444

[ijjk]

Change looks good, are we able to add a regression test for this?

[hanneslund]

isError already checks if name and message are there, is the second truthiness check necessary?

[ijjk]

Looks good to drop the redundant checks here 👍

[ijjk]

Changes and added tests look good, thanks!