Enable patterns in IL comparison tests on Windows

This is a follow-up to https://dart-review.googlesource.com/c/sdk/+/287222
which enabled patterns experiment in compare_il script, but not
compare_il.bat.

TEST=ci

Fixes https://github.com/dart-lang/sdk/issues/51694

Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-nnbd-win-release-x64-try
Change-Id: I3a31339d6a17ef62a4b62340993fcff6f97373ee
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/288067
Commit-Queue: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Auto-Submit: Alexander Markov <alexmarkov@google.com>
diff --git a/pkg/vm/tool/compare_il.bat b/pkg/vm/tool/compare_il.bat
index 6384895..bd7ac74 100644
--- a/pkg/vm/tool/compare_il.bat
+++ b/pkg/vm/tool/compare_il.bat
@@ -14,4 +14,4 @@
 
 set DART=%SDK_DIR%/tools/sdks/dart-sdk/bin/dart.exe
 
-"%DART%" %DART_VM_OPTIONS% --enable-experiment=records "%SDK_DIR%/pkg/vm/bin/compare_il.dart" %*
+"%DART%" %DART_VM_OPTIONS% --enable-experiment=records,patterns "%SDK_DIR%/pkg/vm/bin/compare_il.dart" %*