Expose changes in the network quality to the renderers

content/browser/net_info_browsertest.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/command_line.h"
 #include "base/run_loop.h"
 #include "base/strings/string_number_conversions.h"
+#include "base/test/histogram_tester.h"
 #include "build/build_config.h"
+#include "content/browser/net/network_quality_observer_impl.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/test/browser_test_utils.h"
 #include "content/public/test/content_browser_test.h"
 #include "content/public/test/content_browser_test_utils.h"
 #include "content/shell/browser/shell.h"
 #include "net/base/network_change_notifier.h"
 #include "net/base/network_change_notifier_factory.h"
+#include "net/nqe/network_quality_estimator_test_util.h"
 
 namespace content {
 
 class NetInfoBrowserTest : public content::ContentBrowserTest {
  protected:
   void SetUpCommandLine(base::CommandLine* command_line) override {
     // TODO(jkarlin): Once NetInfo is enabled on all platforms remove this
     // switch.
     command_line->AppendSwitch(switches::kEnableNetworkInformation);
 
@@ skipping 108 matching lines @@
   EXPECT_FALSE(RunScriptExtractBool("getOnLine()"));
 
   // Open the same page in a new window on the same process.
   EXPECT_TRUE(ExecuteScript(shell(), "window.open(\"net_info.html\")"));
 
   // The network state should not have reinitialized to what it was when opening
   // the first window (online).
   EXPECT_FALSE(RunScriptExtractBool("getOnLine()"));
 }
 
+// Make sure the changes in the network quality are notified to the render
+// thread.
+IN_PROC_BROWSER_TEST_F(NetInfoBrowserTest, NetworkQualityChangeNotified) {
+  base::HistogramTester histogram_tester;
+  net::TestNetworkQualityEstimator estimator;
+  NetworkQualityObserverImpl impl(&estimator);
+  estimator.NotifyObserversOfRTTOrThroughputEstimatesComputed(
+      net::nqe::internal::NetworkQuality(base::TimeDelta::FromSeconds(1),
+                                         base::TimeDelta::FromSeconds(2), 3));
+
+  NavigateToURL(shell(), content::GetTestUrl("", "net_info.html"));
+
+  FetchHistogramsFromChildProcesses();
+  EXPECT_FALSE(
+      histogram_tester.GetAllSamples("NQE.RenderThreadNotified").empty());
+}
+
 }  // namespace content