Analysis server context ID is now specified by the client.

pkg/analysis_server/test/domain_context_test.dart

Index: pkg/analysis_server/test/domain_context_test.dart
diff --git a/pkg/analysis_server/test/domain_context_test.dart b/pkg/analysis_server/test/domain_context_test.dart
index c66856eb7811879368afea23b378452393d6acbf..10421c73d4d952e33b9a9084a2b92af0a533b761 100644
--- a/pkg/analysis_server/test/domain_context_test.dart
+++ b/pkg/analysis_server/test/domain_context_test.dart
@@ -26,6 +26,8 @@ main() {
 }
 
 class ContextDomainHandlerTest {
+  static int contextIdCounter = 0;
+
   static void applyChanges() {
     AnalysisServer server = new AnalysisServer(new MockServerChannel());
     String contextId = _createContext(server);
@@ -111,14 +113,15 @@ class ContextDomainHandlerTest {
   }
 
   static String _createContext(AnalysisServer server) {
+    String contextId = "context${contextIdCounter++}";
     ServerDomainHandler handler = new ServerDomainHandler(server);
     Request request = new Request('0', ServerDomainHandler.CREATE_CONTEXT_METHOD);
     request.setParameter(ServerDomainHandler.SDK_DIRECTORY_PARAM, sdkPath);
+    request.setParameter(ServerDomainHandler.CONTEXT_ID_PARAM, contextId);
     Response response = handler.handleRequest(request);
     if (response.error != null) {
       fail('Unexpected error: ${response.error.toJson()}');
     }
-    expect(response.error, isNull);
-    return response.getResult(ServerDomainHandler.CONTEXT_ID_RESULT);
+    return contextId;
   }
 }