Moving src/webrtc into src/.

In order to eliminate the WebRTC Subtree mirror in Chromium, 
WebRTC is moving the content of the src/webrtc directory up
to the src/ directory.

NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
TBR=tommi@webrtc.org

Bug: chromium:611808
Change-Id: Iac59c5b51b950f174119565bac87955a7994bc38
Reviewed-on: https://webrtc-review.googlesource.com/1560
Commit-Queue: Mirko Bonadei <mbonadei@webrtc.org>
Reviewed-by: Henrik Kjellander <kjellander@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#19845}

rtc_tools/loopback_test/stat_tracker.js

@@ -0,0 +1,94 @@
+/**
+ * Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
+ *
+ * Use of this source code is governed by a BSD-style license
+ * that can be found in the LICENSE file in the root of the source
+ * tree. An additional intellectual property rights grant can be found
+ * in the file PATENTS.  All contributing project authors may
+ * be found in the AUTHORS file in the root of the source tree.
+ */
+
+// StatTracker is a helper class to keep track of stats on a RTCPeerConnection
+// object. It uses google visualization datatables to keep the recorded samples
+// and simplify plugging them into graphs later.
+//
+// Usage example:
+//   var tracker = new StatTracker(pc, pollInterval);
+//   tracker.recordStat("EstimatedSendBitrate",
+//                      "bweforvideo", "googAvailableSendBandwidth");
+//   ...
+//   tracker.stop();
+//   tracker.dataTable(); // returns the recorded values. In this case
+//   a table with 2 columns { Time, EstimatedSendBitrate } and a row for each
+//   sample taken until stop() was called.
+//
+function StatTracker(pc, pollInterval) {
+  pollInterval = pollInterval || 250;
+
+  var dataTable = new google.visualization.DataTable();
+  var timeColumnIndex = dataTable.addColumn('datetime', 'Time');
+  var recording = true;
+
+  // Set of sampling functions. Functions registered here are called
+  // once per getStats with the given report and a rowIndex for the
+  // sample period so they can extract and record the tracked variables.
+  var samplingFunctions = {};
+
+  // Accessor to the current recorded stats.
+  this.dataTable = function() { return dataTable; }
+
+  // recordStat(varName, recordName, statName) adds a samplingFunction that
+  // records namedItem(recordName).stat(statName) from RTCStatsReport for each
+  // sample into a column named varName in the dataTable.
+  this.recordStat = function (varName, recordName, statName) {
+    var columnIndex = dataTable.addColumn('number', varName);
+    samplingFunctions[varName] = function (report, rowIndex) {
+      var sample;
+      var record = report.namedItem(recordName);
+      if (record) sample = record.stat(statName);
+      dataTable.setCell(rowIndex, columnIndex, sample);
+    }
+  }
+
+  // Stops the polling of stats from the peer connection.
+  this.stop = function() {
+    recording = false;
+  }
+
+  // RTCPeerConnection.getStats is asynchronous. In order to avoid having
+  // too many pending getStats requests going, this code only queues the
+  // next getStats with setTimeout after the previous one returns, instead
+  // of using setInterval.
+  function poll() {
+    pc.getStats(function (report) {
+      if (!recording) return;
+      setTimeout(poll, pollInterval);
+      var result = report.result();
+      if (result.length < 1) return;
+
+      var rowIndex = dataTable.addRow();
+      dataTable.setCell(rowIndex, timeColumnIndex, result[0].timestamp);
+      for (var v in samplingFunctions)
+        samplingFunctions[v](report, rowIndex);
+    });
+  }
+  setTimeout(poll, pollInterval);
+}
+
+/**
+ * Utility method to perform a full join between data tables from StatTracker.
+ */
+function mergeDataTable(dataTable1, dataTable2) {
+  function allColumns(cols) {
+    var a = [];
+    for (var i = 1; i < cols; ++i) a.push(i);
+    return a;
+  }
+  return google.visualization.data.join(
+      dataTable1,
+      dataTable2,
+      'full',
+      [[0, 0]],
+      allColumns(dataTable1.getNumberOfColumns()),
+      allColumns(dataTable2.getNumberOfColumns()));
+}