Use AnalysisOptions.signature as a way to check compatibility.

pkg/analyzer/lib/src/generated/package.dart

Index: pkg/analyzer/lib/src/generated/package.dart
diff --git a/pkg/analyzer/lib/src/generated/package.dart b/pkg/analyzer/lib/src/generated/package.dart
index dddce5a037b4d96b0089fb15ec24b04de6a29720..5983dd3ab9eebaac1af865041edd4c692651614e 100644
--- a/pkg/analyzer/lib/src/generated/package.dart
+++ b/pkg/analyzer/lib/src/generated/package.dart
@@ -158,7 +158,7 @@ class PackageDescription {
   @override
   int get hashCode {
     int hashCode = 0;
-    for (int value in options.encodeCrossContextOptions()) {
+    for (int value in options.signature) {
       hashCode = JenkinsSmiHash.combine(hashCode, value);
     }
     hashCode = JenkinsSmiHash.combine(hashCode, id.hashCode);
@@ -170,9 +170,8 @@ class PackageDescription {
   bool operator ==(Object other) {
     return other is PackageDescription &&
         other.sdk == sdk &&
-        AnalysisOptions.crossContextOptionsEqual(
-            other.options.encodeCrossContextOptions(),
-            options.encodeCrossContextOptions()) &&
+        AnalysisOptions.signaturesEqual(
+            other.options.signature, options.signature) &&
         other.id == id;
   }
 }