Issue 52360. Don't attempt to serialize PatternAssignment.

Bug: https://github.com/dart-lang/sdk/issues/52360
Change-Id: Iaf6fdbc602bd534147d88882fc39db69c3014585
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/302882
Reviewed-by: Samuel Rawlins <srawlins@google.com>
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>
Commit-Queue: Konstantin Shcheglov <scheglov@google.com>

pkg/analyzer/lib/src/summary2/not_serializable_nodes.dart

diff --git a/pkg/analyzer/lib/src/summary2/not_serializable_nodes.dart b/pkg/analyzer/lib/src/summary2/not_serializable_nodes.dart
index b98e883..2c82593 100644
--- a/pkg/analyzer/lib/src/summary2/not_serializable_nodes.dart
+++ b/pkg/analyzer/lib/src/summary2/not_serializable_nodes.dart
@@ -42,6 +42,11 @@
   }
 
   @override
+  void visitPatternAssignment(PatternAssignment node) {
+    result = false;
+  }
+
+  @override
   void visitSwitchExpression(SwitchExpression node) {
     result = false;
   }

pkg/analyzer/test/src/summary/elements_test.dart

diff --git a/pkg/analyzer/test/src/summary/elements_test.dart b/pkg/analyzer/test/src/summary/elements_test.dart
index 5ac5789..8bf204a 100644
--- a/pkg/analyzer/test/src/summary/elements_test.dart
+++ b/pkg/analyzer/test/src/summary/elements_test.dart
@@ -13499,6 +13499,28 @@
 ''');
   }
 
+  test_const_invalid_patternAssignment() async {
+    var library = await buildLibrary('''
+const v = (a,) = (0,);
+''');
+    checkElementText(library, r'''
+library
+  definingUnit
+    topLevelVariables
+      static const v @6
+        type: (int)
+        shouldUseTypeForInitializerInference: false
+        constantInitializer
+          SimpleIdentifier
+            token: _notSerializableExpression @-1
+            staticElement: <null>
+            staticType: null
+    accessors
+      synthetic static get v @-1
+        returnType: (int)
+''');
+  }
+
   test_const_invalid_topLevel() async {
     var library = await buildLibrary(r'''
 const v = 1 + foo();