[co19] Roll co19 to c051b94705832669ea10d6e064e777aad87b0e25

2020-08-24 [email protected] Fixes 921. co19 roll failures fixed
2020-08-24 [email protected] LibTest\io tests fixed to not to fail on tryjobs
2020-08-24 [email protected] Fixes 919. LibTest\isolate\SendPort and LibTest\isolate\Capability tests migrated to null safety
2020-08-24 [email protected] Fixes 918. LibTest\isolate\ReceivePort tests migrated to null safety
2020-08-24 [email protected] LibTest/html tests compile time errors fixed

Failures will be triaged on dart-lang/co19#922.

Change-Id: Ide83f78b0ecfbdde39a6bf3405152020501d2320
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/160060
Reviewed-by: William Hesse <[email protected]>

Author: athomas

DEPS

@@ -44,7 +44,7 @@ vars = {
   # co19 is a cipd package. Use update.sh in tests/co19[_2] to update these
   # hashes. It requires access to the dart-build-access group, which EngProd
   # has.
-  "co19_rev": "28b7e665580cecdf64bc3c81c5b4ed137380c33d",
+  "co19_rev": "c051b94705832669ea10d6e064e777aad87b0e25",
   "co19_2_rev": "e48b3090826cf40b8037648f19d211e8eab1b4b6",
 
   # The internal benchmarks to use. See go/dart-benchmarks-internal