Add start/finish navigation to startup metrics.

chrome/browser/metrics/first_web_contents_profiler.cc

Index: chrome/browser/metrics/first_web_contents_profiler.cc
diff --git a/chrome/browser/metrics/first_web_contents_profiler.cc b/chrome/browser/metrics/first_web_contents_profiler.cc
index 86fd62067fc4039e35f52940c4372c8bfc2e93db..69de1bd51a4be0714df6db48a9affd259427fc45 100644
--- a/chrome/browser/metrics/first_web_contents_profiler.cc
+++ b/chrome/browser/metrics/first_web_contents_profiler.cc
@@ -9,6 +9,7 @@
 #include <string>
 
 #include "base/location.h"
+#include "base/logging.h"
 #include "base/metrics/histogram_macros.h"
 #include "base/process/process_info.h"
 #include "base/single_thread_task_runner.h"
@@ -22,6 +23,7 @@
 #include "components/startup_metric_utils/startup_metric_utils.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/navigation_details.h"
+#include "content/public/browser/navigation_handle.h"
 
 namespace {
 
@@ -120,6 +122,8 @@ FirstWebContentsProfiler::FirstWebContentsProfiler(
       initial_entry_committed_(false),
       collected_paint_metric_(false),
       collected_load_metric_(false),
+      collected_main_navigation_start_metric_(false),
+      collected_main_navigation_finished_metric_(false),
       delegate_(delegate),
       responsiveness_histogram_(NULL),
       responsiveness_1sec_histogram_(NULL),
@@ -183,6 +187,46 @@ void FirstWebContentsProfiler::DocumentOnLoadCompletedInMainFrame() {
     FinishedCollectingMetrics(FinishReason::DONE);
 }
 
+void FirstWebContentsProfiler::DidStartNavigation(
+    content::NavigationHandle* navigation_handle) {
+  if (collected_main_navigation_start_metric_)
+    return;
+  if (startup_metric_utils::WasNonBrowserUIDisplayed()) {
+    FinishedCollectingMetrics(FinishReason::ABANDON_BLOCKING_UI);
+    return;
+  }
+
+  // The first navigation has to be the main frame's.
+  DCHECK(navigation_handle->IsInMainFrame());
+
+  collected_main_navigation_start_metric_ = true;
+  startup_metric_utils::RecordFirstWebContentsMainNavigationStart(
+      base::Time::Now());
+}
+
+void FirstWebContentsProfiler::DidFinishNavigation(
+    content::NavigationHandle* navigation_handle) {
+  if (collected_main_navigation_finished_metric_)
+    return;
+  if (startup_metric_utils::WasNonBrowserUIDisplayed()) {
+    FinishedCollectingMetrics(FinishReason::ABANDON_BLOCKING_UI);
+    return;
+  }
+
+  // The first navigation has to be the main frame's.
+  DCHECK(navigation_handle->IsInMainFrame());
+
+  if (!navigation_handle->HasCommitted() ||
+      navigation_handle->IsErrorPage()) {
+    FinishedCollectingMetrics(FinishReason::ABANDON_NAVIGATION_ERROR);
+    return;
+  }
+
+  collected_main_navigation_finished_metric_ = true;
+  startup_metric_utils::RecordFirstWebContentsMainNavigationFinished(
+      base::Time::Now());
+}
+
 void FirstWebContentsProfiler::NavigationEntryCommitted(

[clamy, 2015/10/28 11:55:59]

I think this can be merged inside DidFinishNavigation:
void FirstWebContentsProfiler::DidFinishNavigation(
 if (collected_main_navigation_finished_metric_) {
   if (navigation_handle->HasCommitted() &&
       !navigation_handle->IsSamePage()) {
     FinishedCollectingMetrics(FinishReason::ABANDON_NEW_NAVIGATION);
   }
   return;
 }
...

This should also allow to get rid of initial_entry_committed_.

[gab, 2015/10/28 20:17:38]

Awesome, done :-)! (also added IsMainFrame() to the check which I think is
required to not trigger on follow-up sub-navigations finishing)

Curious, what does IsSamePage() mean? The method's documentation is not clear to
me (i.e. I tried refreshing a page and clicking on a link to self in a test
page, both times FinishReason::ABANDON_NEW_NAVIGATION triggered (as desired) but
I expected the !IsSamePage() check to skip those).

[Charlie Reis, 2015/10/28 20:58:26]

IsSamePage means you haven't left the current document, such as fragment
navigations (#foo), pushState, replaceState, etc.  Reloads don't count because
they cause the document to be replaced (with a new one from the same URL).

clamy@, maybe you could clarify that in navigation_handle.h?

     const content::LoadCommittedDetails& load_details) {
   // Abandon profiling on any navigation to a different page as it:
@@ -193,7 +237,7 @@ void FirstWebContentsProfiler::NavigationEntryCommitted(
   //       page that does trigger it.
   if (load_details.is_navigation_to_different_page()) {
     if (initial_entry_committed_)
-      FinishedCollectingMetrics(FinishReason::ABANDON_NAVIGATION);
+      FinishedCollectingMetrics(FinishReason::ABANDON_NEW_NAVIGATION);
     else
       initial_entry_committed_ = true;
   }