Initial implementation for 'analysis.setSubscriptions' API.

pkg/analysis_server/test/protocol_test.dart

Index: pkg/analysis_server/test/protocol_test.dart
diff --git a/pkg/analysis_server/test/protocol_test.dart b/pkg/analysis_server/test/protocol_test.dart
index 61ec2b6aba1d8dc1f46085ec87eda027c11ef85c..79c394be1500e1b82f5ca007316df873bb59ecb0 100644
--- a/pkg/analysis_server/test/protocol_test.dart
+++ b/pkg/analysis_server/test/protocol_test.dart
@@ -425,6 +425,32 @@ class RequestDatumTest {
     }).asStringMap(), _throwsInvalidParameter);
     expect(() => makeDatum([]).asStringMap(), _throwsInvalidParameter);
   }
+
+  @runTest
+  static void asStringListMap() {
+    setUp();
+    {
+      var map = {
+        'key1': ['value11', 'value12'],
+        'key2': ['value21', 'value22']
+      };
+      expect(makeDatum(map).asStringListMap(), map);
+    }
+    {
+      var map = {
+        'key1': 10,
+        'key2': 20
+      };
+      expect(() => makeDatum(map).asStringListMap(), _throwsInvalidParameter);
+    }
+    {
+      var map = {
+        'key1': [11, 12],
+        'key2': [21, 22]
+      };
+      expect(() => makeDatum(map).asStringListMap(), _throwsInvalidParameter);
+    }
+  }
 }
 
 class ResponseTest {