[TooManyTabs] Add TabNavigationThrottle

chrome/browser/resource_coordinator/tab_manager_web_contents_data.cc

Index: chrome/browser/resource_coordinator/tab_manager_web_contents_data.cc
diff --git a/chrome/browser/resource_coordinator/tab_manager_web_contents_data.cc b/chrome/browser/resource_coordinator/tab_manager_web_contents_data.cc
index af91c398ac0163e9f1f4f1a940b81e12767f7434..11e41e30049e483c4e85dc9ead2178a0800e642a 100644
--- a/chrome/browser/resource_coordinator/tab_manager_web_contents_data.cc
+++ b/chrome/browser/resource_coordinator/tab_manager_web_contents_data.cc
@@ -9,6 +9,7 @@
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/engagement/site_engagement_service.h"
 #include "chrome/browser/profiles/profile.h"
+#include "chrome/browser/resource_coordinator/tab_manager.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/web_contents.h"
 
@@ -32,6 +33,15 @@ void TabManager::WebContentsData::DidStartLoading() {
   // Marks the tab as no longer discarded if it has been reloaded from another
   // source (ie: context menu).
   SetDiscardState(false);
+  tab_data_.has_finished_loading = false;
+}
+
+void TabManager::WebContentsData::DidStopLoading() {

[nasko, 2017/06/12 23:22:02]

Just FYI, DidStartLoading and DidStopLoading can be fired if an iframe navigates
inside a WebContents, so it doesn't imply the main document is navigating away.

[Zhen Wang, 2017/06/13 23:33:20]

Thanks for pointing this out! I switched to use DidStartNavigation, which
contains navigation_handle, so we can check if it is main frame. DidStopLoading
here is fine as a temporary solution. We will switch to use tab done loading
signal later.

+  // TODO(zhenw): Switch to use tab done loading signal when it is ready.

[Charlie Reis, 2017/06/10 00:53:36]

What does this refer to?  Is there a bug number you can cite?

[Zhen Wang, 2017/06/13 23:33:20]

It is actually using the same bug number as this CL. lpy@ is actively working on
that right now and here is a design doc:
https://docs.google.com/document/d/1l98CsGcTqSTLDsYTJsdj5-_Pn1yq03eqYuvF-0F_F0k/

+  if (!tab_data_.has_finished_loading) {
+    tab_data_.has_finished_loading = true;
+    g_browser_process->GetTabManager()->HasFinishedLoadingTab(web_contents());
+  }
 }
 
 void TabManager::WebContentsData::WebContentsDestroyed() {
@@ -168,6 +178,7 @@ TabManager::WebContentsData::Data::Data()
     : is_discarded(false),
       discard_count(0),
       is_recently_audible(false),
+      has_finished_loading(false),
       last_audio_change_time(TimeTicks::UnixEpoch()),
       last_discard_time(TimeTicks::UnixEpoch()),
       last_reload_time(TimeTicks::UnixEpoch()),
@@ -178,6 +189,7 @@ TabManager::WebContentsData::Data::Data()
 bool TabManager::WebContentsData::Data::operator==(const Data& right) const {
   return is_discarded == right.is_discarded &&
          is_recently_audible == right.is_recently_audible &&
+         has_finished_loading == right.has_finished_loading &&
          last_audio_change_time == right.last_audio_change_time &&
          last_discard_time == right.last_discard_time &&
          last_reload_time == right.last_reload_time &&