Remove keep-alive impulse IPCs from NaCl modules.

extensions/browser/process_manager.h

Index: extensions/browser/process_manager.h
diff --git a/extensions/browser/process_manager.h b/extensions/browser/process_manager.h
index 156955367bea2757770de82c270d1c6d95e7b490..7d6e4223875672f22692f5dcf83da0ec4c8145f5 100644
--- a/extensions/browser/process_manager.h
+++ b/extensions/browser/process_manager.h
@@ -125,16 +125,6 @@ class ProcessManager : public KeyedService,
   void IncrementLazyKeepaliveCount(const Extension* extension);
   void DecrementLazyKeepaliveCount(const Extension* extension);
 
-  // Keeps a background page alive. Unlike IncrementLazyKeepaliveCount, these
-  // impulses will only keep the page alive for a limited amount of time unless
-  // called regularly.
-  void KeepaliveImpulse(const Extension* extension);
-
-  // Triggers a keepalive impulse for a plugin (e.g NaCl).
-  static void OnKeepaliveFromPlugin(int render_process_id,
-                                    int render_frame_id,
-                                    const std::string& extension_id);
-
   // Handles a response to the ShouldSuspend message, used for lazy background
   // pages.
   void OnShouldSuspendAck(const std::string& extension_id,
@@ -157,14 +147,6 @@ class ProcessManager : public KeyedService,
   // Called on shutdown to close our extension hosts.
   void CloseBackgroundHosts();
 
-  // Sets callbacks for testing keepalive impulse behavior.
-  using ImpulseCallbackForTesting =
-      base::Callback<void(const std::string& extension_id)>;
-  void SetKeepaliveImpulseCallbackForTesting(
-      const ImpulseCallbackForTesting& callback);
-  void SetKeepaliveImpulseDecrementCallbackForTesting(
-      const ImpulseCallbackForTesting& callback);
-
   // EventPageTracker implementation.
   bool IsEventPageSuspended(const std::string& extension_id) override;
   bool WakeEventPage(const std::string& extension_id,
@@ -262,9 +244,6 @@ class ProcessManager : public KeyedService,
   // |extension_id| known to have a lazy background page.
   void DecrementLazyKeepaliveCount(const std::string& extension_id);
 
-  // Checks if keepalive impulses have occured, and adjusts keep alive count.
-  void OnKeepaliveImpulseCheck();
-
   // These are called when the extension transitions between idle and active.
   // They control the process of closing the background page when idle.
   void OnLazyBackgroundPageIdle(const std::string& extension_id,
@@ -312,9 +291,6 @@ class ProcessManager : public KeyedService,
   // True if we have created the startup set of background hosts.
   bool startup_background_hosts_created_;
 
-  ImpulseCallbackForTesting keepalive_impulse_callback_for_testing_;
-  ImpulseCallbackForTesting keepalive_impulse_decrement_callback_for_testing_;
-
   base::ObserverList<ProcessManagerObserver> observer_list_;
 
   // ID Counter used to set ProcessManager::BackgroundPageData close_sequence_id