refactor(core): bake single-thread assumptions into spawn/spawn_blocking (#19056)

Partially supersedes #19016.

This migrates `spawn` and `spawn_blocking` to `deno_core`, and removes
the requirement for `spawn` tasks to be `Send` given our single-threaded
executor.

While we don't need to technically do anything w/`spawn_blocking`, this
allows us to have a single `JoinHandle` type that works for both cases,
and allows us to more easily experiment with alternative
`spawn_blocking` implementations that do not require tokio (ie: rayon).

Async ops (+~35%):

Before: 

```
time 1310 ms rate 763358
time 1267 ms rate 789265
time 1259 ms rate 794281
time 1266 ms rate 789889
```

After:

```
time 956 ms rate 1046025
time 954 ms rate 1048218
time 924 ms rate 1082251
time 920 ms rate 1086956
```

HTTP serve (+~4.4%):

Before:

```
Running 10s test @ http://localhost:4500
  2 threads and 10 connections
  Thread Stats   Avg      Stdev     Max   +/- Stdev
    Latency    68.78us   19.77us   1.43ms   86.84%
    Req/Sec    68.78k     5.00k   73.84k    91.58%
  1381833 requests in 10.10s, 167.36MB read
Requests/sec: 136823.29
Transfer/sec:     16.57MB
```

After:

```
Running 10s test @ http://localhost:4500
  2 threads and 10 connections
  Thread Stats   Avg      Stdev     Max   +/- Stdev
    Latency    63.12us   17.43us   1.11ms   85.13%
    Req/Sec    71.82k     3.71k   77.02k    79.21%
  1443195 requests in 10.10s, 174.79MB read
Requests/sec: 142921.99
Transfer/sec:     17.31MB
```

Suggested-By: alice@ryhl.io
Co-authored-by: Bartek Iwańczuk <biwanczuk@gmail.com>

1 files changed, 8 insertions, 6 deletions

diff --git a/cli/lsp/testing/execution.rs b/cli/lsp/testing/execution.rs
index 4834cd0c9..ce8c8b5ac 100644
--- a/cli/lsp/testing/execution.rs
+++ b/cli/lsp/testing/execution.rs
@@ -24,9 +24,11 @@ use deno_core::futures::stream;
 use deno_core::futures::StreamExt;
 use deno_core::parking_lot::Mutex;
 use deno_core::parking_lot::RwLock;
+use deno_core::task::spawn;
+use deno_core::task::spawn_blocking;
 use deno_core::ModuleSpecifier;
 use deno_runtime::permissions::Permissions;
-use deno_runtime::tokio_util::run_local;
+use deno_runtime::tokio_util::create_and_run_current_thread;
 use indexmap::IndexMap;
 use std::collections::HashMap;
 use std::collections::HashSet;
@@ -284,7 +286,7 @@ impl TestRun {
       };
       let token = self.token.clone();
 
-      tokio::task::spawn_blocking(move || {
+      spawn_blocking(move || {
         if fail_fast_tracker.should_stop() {
           return Ok(());
         }
@@ -292,13 +294,13 @@ impl TestRun {
         let file_result = if token.is_cancelled() {
           Ok(())
         } else {
-          run_local(test::test_specifier(
-            &worker_factory,
+          create_and_run_current_thread(test::test_specifier(
+            worker_factory,
             permissions,
             specifier,
             sender.clone(),
             fail_fast_tracker,
-            &test::TestSpecifierOptions {
+            test::TestSpecifierOptions {
               filter,
               shuffle: None,
               trace_ops: false,
@@ -331,7 +333,7 @@ impl TestRun {
     ));
 
     let handler = {
-      tokio::task::spawn(async move {
+      spawn(async move {
         let earlier = Instant::now();
         let mut summary = test::TestSummary::new();
         let mut used_only = false;