Update dispatch_event to take Event or CustomEvent #1990

Job	Run time
build_examples	3m 54s
build_benchmarks	50s
Check	54s
build_nightly	1m 35s
Verify that web-sys is compiled correctly	42s
Clippy	6m 33s
dist_linux_x86_64_musl	2m 18s
dist_linux_aarch64_gnu	2m 43s
dist_macos_aarch64	1m 10s
dist_macos_x86_64	1m 13s
dist_windows	3m 24s
doc_api	1m 8s
doc_book	11s
Rustfmt	8s
Build and test the deno example	46s
Run js-sys crate tests	2m 2s
Run native tests	1m 42s
Run wasm-bindgen crate tests with multithreading enabled	1m 18s
Test TypeScript output of wasm-bindgen	1m 14s
Run UI compile-fail tests	41s
Run wasm-bindgen crate tests (unix)	7m 14s
Run web-sys crate tests	6m 57s
Run wasm-bindgen-webidl crate tests	1m 56s
test_examples	1m 47s
deploy	38s
	52m 58s

Provide feedback