Rely directly on performance.now

[developit]

React doesn't export the scheduler methods or constants from react or react-dom.

[github-actions]

Size Change: -366 B (0%)

Total Size: 42 kB

Filename	Size	Change
compat/dist/compat.js	3.39 kB	-114 B (3%)
compat/dist/compat.module.js	3.38 kB	-135 B (3%)
compat/dist/compat.umd.js	3.44 kB	-117 B (3%)

ℹ️ View Unchanged

Filename	Size	Change
debug/dist/debug.js	2.99 kB	0 B
debug/dist/debug.module.js	2.98 kB	0 B
debug/dist/debug.umd.js	3.07 kB	0 B
devtools/dist/devtools.js	232 B	0 B
devtools/dist/devtools.module.js	241 B	0 B
devtools/dist/devtools.umd.js	308 B	0 B
dist/preact.js	3.97 kB	0 B
dist/preact.min.js	4.01 kB	0 B
dist/preact.module.js	4 kB	0 B
dist/preact.umd.js	4.05 kB	0 B
hooks/dist/hooks.js	1.13 kB	0 B
hooks/dist/hooks.module.js	1.15 kB	0 B
hooks/dist/hooks.umd.js	1.2 kB	0 B
jsx-runtime/dist/jsxRuntime.js	327 B	0 B
jsx-runtime/dist/jsxRuntime.module.js	335 B	0 B
jsx-runtime/dist/jsxRuntime.umd.js	405 B	0 B
test-utils/dist/testUtils.js	437 B	0 B
test-utils/dist/testUtils.module.js	439 B	0 B
test-utils/dist/testUtils.umd.js	515 B	0 B

_{compressed-size-action}

[marvinhagemeister]

Let's get the CI green and then this is ready to be merged 👍

[coveralls]

Coverage decreased (-0.6%) to 98.876% when pulling 068a233 on scheduler-slimdown into ec88035 on master.