Bump webdev to 4fc5d8c1941403200b09e51d4d89ae8cb8c07bd3

Changes:
```
> git log --format="%C(auto) %h %s" 7f376d2..4fc5d8c
 https://dart.googlesource.com/webdev.git/+/4fc5d8c1 update a call to the package:shelf_web_socket webSocketHandler() function (2659)
 https://dart.googlesource.com/webdev.git/+/cb68ac37 Update builds for SDK assets in tests (2653)
 https://dart.googlesource.com/webdev.git/+/bd0bcb84 Support running DWDS without a Chrome Debug Port (web-socket-based) (2639)
 https://dart.googlesource.com/webdev.git/+/84ebf86d Change tls_test.dart to _webdevSoundSmoke fixture (2652)
 https://dart.googlesource.com/webdev.git/+/e95af5fd Wait until all scripts are parsed before recomputing metadata on a hot reload (2650)
 https://dart.googlesource.com/webdev.git/+/4dbddc8f Address flakes from using temp directory to run tests (2649)
 https://dart.googlesource.com/webdev.git/+/b61423d6 Invalidate caches after a hot reload (2641)
 https://dart.googlesource.com/webdev.git/+/f9f8e130 Add tests covering the ability to debug dot shorthands (2636)
 https://dart.googlesource.com/webdev.git/+/2172ba70 Support breakpoints for hot reload (2627)

```

Diff: https://dart.googlesource.com/webdev.git/+/7f376d242709e933fff70610503d0c5c09b2e17e..4fc5d8c1941403200b09e51d4d89ae8cb8c07bd3/
Change-Id: I450b5116c637e7de62fc80d083f24fc1edbf40e6
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/443340
Commit-Queue: Konstantin Shcheglov <[email protected]>
Auto-Submit: Devon Carew <[email protected]>
Reviewed-by: Konstantin Shcheglov <[email protected]>

Author: devoncarew

DEPS

@@ -150,7 +150,7 @@ vars = {
   "tools_rev": "2a2a2d611f2b98888bb6a93b03aa350c97310d87",
   "vector_math_rev": "13f185f7e97d559e003f5ac79201da12f9a01049",
   "web_rev": "da1dd5d7701d5f2ae9be380ba7de1e3a3201cc64",
-  "webdev_rev": "7f376d242709e933fff70610503d0c5c09b2e17e",
+  "webdev_rev": "4fc5d8c1941403200b09e51d4d89ae8cb8c07bd3",
   "webdriver_rev": "cfab787b30fbfb5509f9fc45cfce51157fb9f369",
   "webkit_inspection_protocol_rev": "effa75205516757795683d527c3dea9546eb0c32",