DevTools: expose network idle times in the detector.

Change-Id: Ife445be39e0c6be0cec0abfc154c700b275b7433
Reviewed-on: https://chromium-review.googlesource.com/721802Reviewed-by: Andrey Lushnikov <lushnikov@chromium.org>
Commit-Queue: Pavel Feldman <pfeldman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#509410}

third_party/WebKit/Source/core/loader/DocumentLoader.cpp

@@ -50,6 +50,7 @@
 #include "core/inspector/MainThreadDebugger.h"
 #include "core/loader/FrameFetchContext.h"
 #include "core/loader/FrameLoader.h"
+#include "core/loader/IdlenessDetector.h"
 #include "core/loader/LinkLoader.h"
 #include "core/loader/NetworkHintsInterface.h"
 #include "core/loader/ProgressTracker.h"
@@ -941,6 +942,7 @@ void DocumentLoader::WillCommitNavigation() {
   if (GetFrameLoader().StateMachine()->CreatingInitialEmptyDocument())
     return;
   probe::willCommitLoad(frame_, this);
+  frame_->GetIdlenessDetector()->WillCommitLoad();
 }
 
 void DocumentLoader::DidCommitNavigation() {

third_party/WebKit/Source/core/loader/IdlenessDetector.cpp

@@ -19,6 +19,11 @@ void IdlenessDetector::Shutdown() {
   local_frame_ = nullptr;
 }
 
+void IdlenessDetector::WillCommitLoad() {
+  network_2_quiet_start_time_ = 0;
+  network_0_quiet_start_time_ = 0;
+}
+
 void IdlenessDetector::DomContentLoadedEventFired() {
   if (!local_frame_)
     return;
@@ -100,6 +105,14 @@ void IdlenessDetector::OnDidLoadResource() {
   }
 }
 
+double IdlenessDetector::GetNetworkAlmostIdleTime() {
+  return network_2_quiet_start_time_;
+}
+
+double IdlenessDetector::GetNetworkIdleTime() {
+  return network_0_quiet_start_time_;
+}
+
 void IdlenessDetector::WillProcessTask(double start_time) {
   // If we have idle time and we are kNetworkQuietWindowSeconds seconds past it,
   // emit idle signals.

third_party/WebKit/Source/core/loader/IdlenessDetector.h

@@ -30,12 +30,16 @@ class CORE_EXPORT IdlenessDetector
   explicit IdlenessDetector(LocalFrame*);
 
   void Shutdown();
+  void WillCommitLoad();
   void DomContentLoadedEventFired();
   // TODO(lpy) Don't need to pass in fetcher once the command line of disabling
   // PlzNavigate is removed.
   void OnWillSendRequest(ResourceFetcher*);
   void OnDidLoadResource();
 
+  double GetNetworkAlmostIdleTime();
+  double GetNetworkIdleTime();
+
   DECLARE_TRACE();
 
  private:
@@ -60,8 +64,8 @@ class CORE_EXPORT IdlenessDetector
   double network_0_quiet_ = 0;
   double network_2_quiet_ = 0;
   // Record the actual start time of network quiet.
-  double network_0_quiet_start_time_;
-  double network_2_quiet_start_time_;
+  double network_0_quiet_start_time_ = 0;
+  double network_2_quiet_start_time_ = 0;
   TaskRunnerTimer<IdlenessDetector> network_quiet_timer_;
 };