File-based and multicast InstrumentationServer implementations.

pkg/analyzer/lib/instrumentation/instrumentation.dart

Index: pkg/analyzer/lib/instrumentation/instrumentation.dart
diff --git a/pkg/analyzer/lib/instrumentation/instrumentation.dart b/pkg/analyzer/lib/instrumentation/instrumentation.dart
index 77547fbee5267f77df30737fd4b219a97465d5e4..a3c13768a9dbe8292b65ea0e15caad57270b9e69 100644
--- a/pkg/analyzer/lib/instrumentation/instrumentation.dart
+++ b/pkg/analyzer/lib/instrumentation/instrumentation.dart
@@ -186,3 +186,33 @@ class InstrumentationService {
     return object.toString();
   }
 }
+
+/**
+ * An [InstrumentationServer] that sends messages to multiple instances.
+ */
+class MulticastInstrumentationServer implements InstrumentationServer {
+  final List<InstrumentationServer> _servers;
+
+  MulticastInstrumentationServer(this._servers);
+
+  @override
+  void log(String message) {
+    for (InstrumentationServer server in _servers) {
+      server.log(message);
+    }
+  }
+
+  @override
+  void logWithPriority(String message) {
+    for (InstrumentationServer server in _servers) {
+      server.logWithPriority(message);
+    }
+  }
+
+  @override
+  void shutdown() {
+    for (InstrumentationServer server in _servers) {
+      server.shutdown();
+    }
+  }
+}