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 a95ff37d65df883ea517cd442d3dd8f612f1e33f..ea8f6f8bf1c7c47c1eb6a79f2ec3be3375e26c05 100644
--- a/chrome/browser/metrics/first_web_contents_profiler.cc
+++ b/chrome/browser/metrics/first_web_contents_profiler.cc
@@ -22,6 +22,7 @@
 #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 {
 
@@ -116,6 +117,8 @@ 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),
       responsiveness_histogram_(NULL),
       responsiveness_1sec_histogram_(NULL),
       responsiveness_10sec_histogram_(NULL),
@@ -178,6 +181,43 @@ 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;
+  }
+
+  if (navigation_handle->IsInMainFrame()) {

[clamy, 2015/10/26 17:51:42]

I think you could just DCHECK(navigation_handle->IsInMainFrame()) here.
You should not be getting a subframe navigation before a main frame navigation.

[gab, 2015/10/27 15:56:15]

Done.

+    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;
+  }
+
+  if (navigation_handle->IsInMainFrame()) {

[clamy, 2015/10/26 17:51:42]

Same here, DCHECK(navigation_handle->IsInMainFrame()) should suffice: you can't
have a subframe navigation start before the main frame navigation has committed.

[gab, 2015/10/27 15:56:15]

Done.

+    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(
     const content::LoadCommittedDetails& load_details) {
   // Abandon profiling on any navigation to a different page as it:
@@ -188,7 +228,7 @@ 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;
   }