Rev DevTools in DEPS

Change-Id: Ie46010dceca3af75fe7a531035e05e433728d52d
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/393904
Reviewed-by: Elliott Brooks <elliottbrooks@google.com>
Commit-Queue: Kenzie Davisson <kenzieschmoll@google.com>

DEPS

@@ -102,7 +102,7 @@ vars = {
   "boringssl_rev": "2db0eb3f96a5756298dcd7f9319e56a98585bd10",
   "browser-compat-data_tag": "ac8cae697014da1ff7124fba33b0b4245cc6cd1b", # v1.0.22
   "cpu_features_rev": "936b9ab5515dead115606559502e3864958f7f6e",
-  "devtools_rev": "f7091d2c0d037f7daf91315ec3da00294d380a8d",
+  "devtools_rev": "3642846c465888b0c56271fe9265a0901f1803f6",
   "icu_rev": "43953f57b037778a1b8005564afabe214834f7bd",
   "jinja2_rev": "2222b31554f03e62600cd7e383376a7c187967a1",
   "libcxx_rev": "44079a4cc04cdeffb9cfe8067bfb3c276fb2bab0",