Keep all type arguments in summaries - dynamic or not.

pkg/analyzer/lib/src/summary/summarize_elements.dart

Index: pkg/analyzer/lib/src/summary/summarize_elements.dart
diff --git a/pkg/analyzer/lib/src/summary/summarize_elements.dart b/pkg/analyzer/lib/src/summary/summarize_elements.dart
index 92388eeb85bfe915b1ae28e250cd7ecaeeff7371..3e48a4ed0d71db7de12256f8743ed3552b5a801e 100644
--- a/pkg/analyzer/lib/src/summary/summarize_elements.dart
+++ b/pkg/analyzer/lib/src/summary/summarize_elements.dart
@@ -1072,20 +1072,9 @@ class _CompilationUnitSerializer {
       }
       List<DartType> typeArguments = getTypeArguments(type);
       if (typeArguments != null) {
-        // Trailing type arguments of type 'dynamic' should be omitted.
-        int numArgsToSerialize = typeArguments.length;
-        while (numArgsToSerialize > 0 &&
-            typeArguments[numArgsToSerialize - 1].isDynamic) {
-          --numArgsToSerialize;
-        }
-        if (numArgsToSerialize > 0) {
-          List<EntityRefBuilder> serializedArguments = <EntityRefBuilder>[];
-          for (int i = 0; i < numArgsToSerialize; i++) {
-            serializedArguments
-                .add(serializeTypeRef(typeArguments[i], context));
-          }
-          b.typeArguments = serializedArguments;
-        }
+        b.typeArguments = typeArguments
+            .map((typeArgument) => serializeTypeRef(typeArgument, context))
+            .toList();
       }
     }
     return b;