Skip VM tests that hang on Windows

Three dart:io tests in the co19 suite are hanging, causing
test infrastructure failures. Skipping them until the problem is fixed.

BUG=dart-lang/sdk#32138

Change-Id: I5102eef49bf094158535aa2b938930994d4df4dd
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/169880
Reviewed-by: Martin Kustermann <kustermann@google.com>

Author: whesse

tests/co19/co19-runtime.status

@@ -6,6 +6,10 @@
 LibTest/core/Uri/hasEmptyPath_A01_t01: RuntimeError
 LibTest/core/Uri/parse_A05_t01: RuntimeError
 
+[ $system == windows ]
+LibTest/io/Stdin/readByteSync_A01_t01: Skip # Issue 43645
+LibTest/io/Stdin/readByteSync_A01_t02: Skip # Issue 43645
+
 [ $arch == simarm64 && $runtime == dart_precompiled ]
 LibTest/async/Stream/Stream.periodic_all_t02: Skip # Issue 42898
 

tests/co19_2/co19_2-runtime.status

@@ -6,6 +6,9 @@
 LibTest/core/Uri/hasEmptyPath_A01_t01: RuntimeError
 LibTest/core/Uri/parse_A05_t01: RuntimeError
 
+[ $system == windows ]
+LibTest/io/ProcessResult/exitCode_A01_t02: Skip # Issue 43645
+
 [ $compiler != dart2js && $runtime != none && $runtime != vm && !$checked ]
 LibTest/async/Future/catchError_A03_t05: RuntimeError