Make HTTP server close sockets when closed in idle state

sdk/lib/io/http.dart

Index: sdk/lib/io/http.dart
diff --git a/sdk/lib/io/http.dart b/sdk/lib/io/http.dart
index 79d16af00d8d3a0efc5bd4b63975e7197c65623c..bcfa93302b8f713c737c605b756584dec5068285 100644
--- a/sdk/lib/io/http.dart
+++ b/sdk/lib/io/http.dart
@@ -117,6 +117,41 @@ abstract class HttpServer {
    * is 20 minutes.
    */
   set sessionTimeout(int timeout);
+
+  /**
+   * Returns a [:HttpConnectionsInfo:] object with an overview of the
+   * current connection handled by the server.
+   */
+  HttpConnectionsInfo connectionsInfo();
+}
+
+
+/**
+ * Overview information of the [:HttpServer:] socket connections.
+ */
+class HttpConnectionsInfo {
+  /**
+   * Total number of socket connections.
+   */
+  int total = 0;
+
+  /**
+   * Number of active connections where actual request/response
+   * processing is active.
+   */
+  int active = 0;
+
+  /**
+   * Number of idle connections held by clients as persistent connections.
+   */
+  int idle = 0;
+
+  /**
+   * Number of connections which are preparing to close. Note: These
+   * connections are also part of the [:active:] count as they might
+   * still be sending data to the client before finally closing.
+   */
+  int closing = 0;
 }