Make LoadMonitoringExtensionHostQueue remove itself as an ExtensionHost observer at the correct tim…

extensions/browser/load_monitoring_extension_host_queue.h

Index: extensions/browser/load_monitoring_extension_host_queue.h
diff --git a/extensions/browser/load_monitoring_extension_host_queue.h b/extensions/browser/load_monitoring_extension_host_queue.h
index cef3242138a2dc50278618f38a958a66d1f20e18..6876399bd89a9d53f9e7f30474a6e88f540130f6 100644
--- a/extensions/browser/load_monitoring_extension_host_queue.h
+++ b/extensions/browser/load_monitoring_extension_host_queue.h
@@ -29,7 +29,7 @@ class LoadMonitoringExtensionHostQueue
   // monitoring has finished (timeout has elapsed and UMA is logged).
   using FinishedCallback = base::Callback<void(size_t,  // num_queued
                                                size_t,  // max_loaded
-                                               size_t,  // max_in_queue
+                                               size_t,  // max_awaiting_loading
                                                size_t   // max_active_loading
                                                )>;
   LoadMonitoringExtensionHostQueue(scoped_ptr<ExtensionHostQueue> delegate,
@@ -72,9 +72,6 @@ class LoadMonitoringExtensionHostQueue
   void StartMonitoringHost(const DeferredStartRenderHost* host);
   void FinishMonitoringHost(const DeferredStartRenderHost* host);
 
-  // Removes |host| from the internal |in_queue_| tracking.
-  void RemoveFromQueue(const DeferredStartRenderHost* host);
-
   // Called when monitoring should finish. Metrics are recorded, and from this
   // point on no monitoring will take place.
   void FinishMonitoring();
@@ -89,8 +86,8 @@ class LoadMonitoringExtensionHostQueue
   // A callback to run when monitoring has finished. Intended for testing.
   FinishedCallback finished_callback_;
 
-  // The hosts which are in the delegate's queue.
-  std::set<DeferredStartRenderHost*> in_queue_;
+  // The hosts which are waiting to start loading.
+  std::set<const DeferredStartRenderHost*> awaiting_loading_;
   // The hosts which are currently loading.
   std::set<const DeferredStartRenderHost*> active_loading_;
 
@@ -102,8 +99,8 @@ class LoadMonitoringExtensionHostQueue
   size_t num_queued_;
   // The total number of hosts that started loading.
   size_t num_loaded_;
-  // The maximum number of hosts in the queue at any time.
-  size_t max_in_queue_;
+  // The maximum number of hosts waiting to load at the same time.
+  size_t max_awaiting_loading_;
   // The maximum number of hosts that were loading at the same time.
   size_t max_active_loading_;