Report incremental/full analysis performance via instrumentation.

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 65b47c13b4c824a94f2602e2422ced27dc3b5617..2cc18aeaa0d3a56e9ce133c1a412ee18d722332c 100644
--- a/pkg/analyzer/lib/instrumentation/instrumentation.dart
+++ b/pkg/analyzer/lib/instrumentation/instrumentation.dart
@@ -5,6 +5,14 @@
 library instrumentation;
 
 /**
+ * A container with analysis performance constants.
+ */
+class AnalysisPerformanceKind {
+  static const String FULL = 'analysis_full';
+  static const String INCREMENTAL = 'analysis_incremental';
+}
+
+/**
  * The interface used by client code to communicate with an instrumentation
  * server.
  */
@@ -49,6 +57,7 @@ class InstrumentationService {
   static const String TAG_EXCEPTION = 'Ex';
   static const String TAG_LOG_ENTRY = 'Log';
   static const String TAG_NOTIFICATION = 'Noti';
+  static const String TAG_PERFORMANCE = 'Perf';
   static const String TAG_REQUEST = 'Req';
   static const String TAG_RESPONSE = 'Res';
   static const String TAG_VERSION = 'Ver';
@@ -108,6 +117,18 @@ class InstrumentationService {
   }
 
   /**
+   * Log the given performance fact.
+   */
+  void logPerformance(String kind, Stopwatch sw, String message) {
+    sw.stop();
+    String elapsed = sw.elapsedMilliseconds.toString();
+    if (_instrumentationServer != null) {
+      _instrumentationServer.log(
+          _join([TAG_PERFORMANCE, kind, elapsed, message]));
+    }
+  }
+
+  /**
    * Log that the given priority [exception] was thrown, with the given
    * [stackTrace].
    */