Pass code as buffer to swc minify

[padmaia]

This should fix this: https://github.com/vercel/next.js/pull/28883/checks?check_run_id=3560578176#step:4:353

Bug

• Related issues linked using fixes #number
• Integration tests added
• Errors have helpful link attached, see contributing.md

Feature

• Implements an existing feature request or RFC. Make sure the feature request has been accepted for implementation before opening a PR.
• Related issues linked using fixes #number
• Integration tests added
• Documentation added
• Telemetry added. In case of a feature if it's used or not.
• Errors have helpful link attached, see contributing.md

Documentation / Examples

• Make sure the linting passes

[ijjk]

Stats from current PR

Default Build (Decrease detected ✓)

General Overall increase ⚠️

	vercel/next.js canary	padmaia/next.js fix/swc-minify-buffer	Change
buildDuration	16.5s	16.4s	-70ms
buildDurationCached	4.2s	4s	-140ms
nodeModulesSize	47 MB	47 MB	⚠️ +40 B

Page Load Tests Overall decrease ⚠️

	vercel/next.js canary	padmaia/next.js fix/swc-minify-buffer	Change
/ failed reqs	0	0	✓
/ total time (seconds)	3.602	3.633	⚠️ +0.03
/ avg req/sec	694.07	688.17	⚠️ -5.9
/error-in-render failed reqs	0	0	✓
/error-in-render total time (seconds)	2.009	2.008	0
/error-in-render avg req/sec	1244.7	1244.75	+0.05

Client Bundles (main, webpack, commons)

	vercel/next.js canary	padmaia/next.js fix/swc-minify-buffer	Change
745.HASH.js gzip	179 B	179 B	✓
framework-HASH.js gzip	42.2 kB	42.2 kB	✓
main-HASH.js gzip	26.6 kB	26.6 kB	✓
webpack-HASH.js gzip	1.45 kB	1.45 kB	✓
Overall change	70.4 kB	70.4 kB	✓

Legacy Client Bundles (polyfills)

	vercel/next.js canary	padmaia/next.js fix/swc-minify-buffer	Change
polyfills-a4..dd70.js gzip	31 kB	31 kB	✓
Overall change	31 kB	31 kB	✓

Client Pages

	vercel/next.js canary	padmaia/next.js fix/swc-minify-buffer	Change
_app-HASH.js gzip	979 B	979 B	✓
_error-HASH.js gzip	194 B	194 B	✓
amp-HASH.js gzip	312 B	312 B	✓
css-HASH.js gzip	329 B	329 B	✓
dynamic-HASH.js gzip	2.67 kB	2.67 kB	✓
head-HASH.js gzip	351 B	351 B	✓
hooks-HASH.js gzip	918 B	918 B	✓
image-HASH.js gzip	4.14 kB	4.14 kB	✓
index-HASH.js gzip	261 B	261 B	✓
link-HASH.js gzip	1.66 kB	1.66 kB	✓
routerDirect..HASH.js gzip	318 B	318 B	✓
script-HASH.js gzip	387 B	387 B	✓
withRouter-HASH.js gzip	320 B	320 B	✓
bb14e60e810b..30f.css gzip	125 B	125 B	✓
Overall change	13 kB	13 kB	✓

Client Build Manifests

	vercel/next.js canary	padmaia/next.js fix/swc-minify-buffer	Change
_buildManifest.js gzip	492 B	492 B	✓
Overall change	492 B	492 B	✓

Rendered Page Sizes

	vercel/next.js canary	padmaia/next.js fix/swc-minify-buffer	Change
index.html gzip	539 B	539 B	✓
link.html gzip	552 B	552 B	✓
withRouter.html gzip	533 B	533 B	✓
Overall change	1.62 kB	1.62 kB	✓

---

Webpack 4 Mode (Increase detected ⚠️)

General Overall increase ⚠️

	vercel/next.js canary	padmaia/next.js fix/swc-minify-buffer	Change
buildDuration	13.9s	13.2s	-766ms
buildDurationCached	5.5s	5.5s	-69ms
nodeModulesSize	47 MB	47 MB	⚠️ +40 B

Page Load Tests Overall increase ✓

	vercel/next.js canary	padmaia/next.js fix/swc-minify-buffer	Change
/ failed reqs	0	0	✓
/ total time (seconds)	3.728	3.654	-0.07
/ avg req/sec	670.62	684.2	+13.58
/error-in-render failed reqs	0	0	✓
/error-in-render total time (seconds)	1.992	1.947	-0.04
/error-in-render avg req/sec	1254.85	1283.76	+28.91

Client Bundles (main, webpack, commons)

	vercel/next.js canary	padmaia/next.js fix/swc-minify-buffer	Change
16.HASH.js gzip	186 B	186 B	✓
677f882d2ed8..HASH.js gzip	14.1 kB	14.1 kB	✓
framework.HASH.js gzip	41.9 kB	41.9 kB	✓
main-HASH.js gzip	13.8 kB	13.8 kB	✓
webpack-HASH.js gzip	1.19 kB	1.19 kB	✓
Overall change	71.2 kB	71.2 kB	✓

Legacy Client Bundles (polyfills)

	vercel/next.js canary	padmaia/next.js fix/swc-minify-buffer	Change
polyfills-a4..dd70.js gzip	31 kB	31 kB	✓
Overall change	31 kB	31 kB	✓

Client Pages

	vercel/next.js canary	padmaia/next.js fix/swc-minify-buffer	Change
_app-HASH.js gzip	964 B	964 B	✓
_error-HASH.js gzip	3.8 kB	3.8 kB	✓
amp-HASH.js gzip	552 B	552 B	✓
css-HASH.js gzip	333 B	333 B	✓
dynamic-HASH.js gzip	2.87 kB	2.87 kB	✓
head-HASH.js gzip	3.06 kB	3.06 kB	✓
hooks-HASH.js gzip	924 B	924 B	✓
index-HASH.js gzip	231 B	231 B	✓
link-HASH.js gzip	1.64 kB	1.64 kB	✓
routerDirect..HASH.js gzip	298 B	298 B	✓
script-HASH.js gzip	3.03 kB	3.03 kB	✓
withRouter-HASH.js gzip	295 B	295 B	✓
30809af5c834..565.css gzip	125 B	125 B	✓
Overall change	18.1 kB	18.1 kB	✓

Client Build Manifests

	vercel/next.js canary	padmaia/next.js fix/swc-minify-buffer	Change
_buildManifest.js gzip	500 B	500 B	✓
Overall change	500 B	500 B	✓

Rendered Page Sizes

	vercel/next.js canary	padmaia/next.js fix/swc-minify-buffer	Change
index.html gzip	585 B	585 B	✓
link.html gzip	597 B	597 B	✓
withRouter.html gzip	578 B	578 B	✓
Overall change	1.76 kB	1.76 kB	✓

Commit: 526124e