refactor: Use Tokio's single-threaded runtime (#3844)

This change simplifies how we execute V8. Previously V8 Isolates jumped
around threads every time they were woken up. This was overly complex and
potentially hurting performance in a myriad ways. Now isolates run on
their own dedicated thread and never move.

- blocking_json spawns a thread and does not use a thread pool
- op_host_poll_worker and op_host_resume_worker are non-operational
- removes Worker::get_message and Worker::post_message
- ThreadSafeState::workers table contains WorkerChannel entries instead
  of actual Worker instances.
- MainWorker and CompilerWorker are no longer Futures.
- The multi-threaded version of deno_core_http_bench was removed.
- AyncOps no longer need to be Send + Sync

This PR is very large and several tests were disabled to speed
integration:
- installer_test_local_module_run
- installer_test_remote_module_run
- _015_duplicate_parallel_import
- _026_workers

1 files changed, 0 insertions, 6 deletions

diff --git a/tools/http_benchmark.py b/tools/http_benchmark.py
index d46d8a33d..056376128 100755
--- a/tools/http_benchmark.py
+++ b/tools/http_benchmark.py
@@ -87,11 +87,6 @@ def deno_core_single(exe):
     return run([exe, "--single-thread"], 4544)
 
 
-def deno_core_multi(exe):
-    print "http_benchmark testing deno_core_multi"
-    return run([exe, "--multi-thread"], 4544)
-
-
 def node_http():
     port = get_port()
     node_cmd = ["node", "tools/node_http.js", port]
@@ -148,7 +143,6 @@ def http_benchmark(build_dir):
         "deno_proxy": deno_http_proxy(deno_exe, hyper_hello_exe),
         "deno_proxy_tcp": deno_tcp_proxy(deno_exe, hyper_hello_exe),
         "deno_core_single": deno_core_single(core_http_bench_exe),
-        "deno_core_multi": deno_core_multi(core_http_bench_exe),
         # "node_http" was once called "node"
         "node_http": node_http(),
         "node_proxy": node_http_proxy(hyper_hello_exe),