3 files changed, 70 insertions, 1 deletions

diff --git a/chrome/renderer/loadtimes_extension_bindings.cc b/chrome/renderer/loadtimes_extension_bindings.cc
index 151e78d..1ad71ed 100644
--- a/chrome/renderer/loadtimes_extension_bindings.cc
+++ b/chrome/renderer/loadtimes_extension_bindings.cc
@@ -134,6 +134,10 @@ class LoadTimesExtensionWrapper : public v8::Extension {
         load_times->Set(
             v8::String::New("wasNpnNegotiated"),
             v8::Boolean::New(navigation_state->was_npn_negotiated()));
+        load_times->Set(
+            v8::String::New("wasAlternateProtocolAvailable"),
+            v8::Boolean::New(
+                navigation_state->was_alternate_protocol_available()));
         return load_times;
       }
     }
diff --git a/chrome/renderer/navigation_state.h b/chrome/renderer/navigation_state.h
index ef3a54e..694057d 100644
--- a/chrome/renderer/navigation_state.h
+++ b/chrome/renderer/navigation_state.h
@@ -223,6 +223,13 @@ class NavigationState : public WebKit::WebDataSource::ExtraData {
   void set_was_npn_negotiated(bool value) { was_npn_negotiated_ = value; }
   bool was_npn_negotiated() const { return was_npn_negotiated_; }
 
+  void set_was_alternate_protocol_available(bool value) {
+    was_alternate_protocol_available_ = value;
+  }
+  bool was_alternate_protocol_available() const {
+    return was_alternate_protocol_available_;
+  }
+
   void set_was_fetched_via_proxy(bool value) {
     was_fetched_via_proxy_ = value;
   }
@@ -287,6 +294,7 @@ class NavigationState : public WebKit::WebDataSource::ExtraData {
   bool was_npn_negotiated_;
   bool was_fetched_via_proxy_;
   bool was_translated_;
+  bool was_alternate_protocol_available_;
 
   DISALLOW_COPY_AND_ASSIGN(NavigationState);
 };
diff --git a/chrome/renderer/render_view.cc b/chrome/renderer/render_view.cc
index 59f600e..aa6fc64 100644
--- a/chrome/renderer/render_view.cc
+++ b/chrome/renderer/render_view.cc
@@ -3005,6 +3005,8 @@ void RenderView::didReceiveResponse(
   // Record page load flags.
   navigation_state->set_was_fetched_via_spdy(response.wasFetchedViaSPDY());
   navigation_state->set_was_npn_negotiated(response.wasNpnNegotiated());
+  navigation_state->set_was_alternate_protocol_available(
+      response.wasAlternateProtocolAvailable());
   navigation_state->set_was_fetched_via_proxy(response.wasFetchedViaProxy());
 
   // Consider loading an alternate error page for 404 responses.
@@ -4715,7 +4717,12 @@ void RenderView::DumpLoadHistograms() const {
   //                and StartToFinish, consider removing one or the other.
   static bool use_spdy_histogram(FieldTrialList::Find("SpdyImpact") &&
       !FieldTrialList::Find("SpdyImpact")->group_name().empty());
-  if (use_spdy_histogram && navigation_state->was_npn_negotiated()) {
+  // Spdy requests triggered by alternate protocol are excluded here.
+  // This is because when alternate protocol is avaiable, FieldTrial will
+  // either use npn_spdy or pure http, not npn_http via TLS. That will cause
+  // bias for npn_spdy and npn_http.
+  if (use_spdy_histogram && navigation_state->was_npn_negotiated() &&
+      !navigation_state->was_alternate_protocol_available()) {
     UMA_HISTOGRAM_ENUMERATION(
         FieldTrial::MakeName("PLT.Abandoned", "SpdyImpact"),
         abandoned_page ? 1 : 0, 2);
@@ -4747,6 +4754,56 @@ void RenderView::DumpLoadHistograms() const {
     }
   }
 
+  // Histograms to compare the impact of alternate protocol: when the
+  // protocol(spdy) is used vs. when it is ignored and http is used.
+  if (navigation_state->was_alternate_protocol_available()) {
+    if (!navigation_state->was_npn_negotiated()) {
+      // This means that even there is alternate protocols for npn_http or
+      // npn_spdy, they are not taken (due to the fieldtrial).
+      switch (load_type) {
+        case NavigationState::LINK_LOAD_NORMAL:
+          PLT_HISTOGRAM(
+              "PLT.StartToFinish_LinkLoadNormal_AlternateProtocol_http",
+              start_to_finish);
+          PLT_HISTOGRAM(
+              "PLT.StartToCommit_LinkLoadNormal_AlternateProtocol_http",
+              start_to_commit);
+          break;
+        case NavigationState::NORMAL_LOAD:
+          PLT_HISTOGRAM(
+              "PLT.StartToFinish_NormalLoad_AlternateProtocol_http",
+              start_to_finish);
+          PLT_HISTOGRAM(
+              "PLT.StartToCommit_NormalLoad_AlternateProtocol_http",
+              start_to_commit);
+          break;
+        default:
+          break;
+      }
+    } else if (navigation_state->was_fetched_via_spdy()) {
+      switch (load_type) {
+        case NavigationState::LINK_LOAD_NORMAL:
+          PLT_HISTOGRAM(
+              "PLT.StartToFinish_LinkLoadNormal_AlternateProtocol_spdy",
+              start_to_finish);
+          PLT_HISTOGRAM(
+              "PLT.StartToCommit_LinkLoadNormal_AlternateProtocol_spdy",
+              start_to_commit);
+          break;
+        case NavigationState::NORMAL_LOAD:
+          PLT_HISTOGRAM(
+              "PLT.StartToFinish_NormalLoad_AlternateProtocol_spdy",
+              start_to_finish);
+          PLT_HISTOGRAM(
+              "PLT.StartToCommit_NormalLoad_AlternateProtocol_spdy",
+              start_to_commit);
+          break;
+        default:
+          break;
+      }
+    }
+  }
+
   // Record page load time and abandonment rates for proxy cases.
   GURL url = GURL(main_frame->url());
   if (navigation_state->was_fetched_via_proxy()) {