Revert of [DevTools] Implement DevToolsManager::Observer which notifies about target updates.

content/browser/devtools/devtools_manager.h

Index: content/browser/devtools/devtools_manager.h
diff --git a/content/browser/devtools/devtools_manager.h b/content/browser/devtools/devtools_manager.h
index 39ba70b1c7417307d3ef0b4354141b0f4fb0385e..0f91f2050ba0f2183f46d307c7888ce1080b7875 100644
--- a/content/browser/devtools/devtools_manager.h
+++ b/content/browser/devtools/devtools_manager.h
@@ -6,37 +6,20 @@
 #define CONTENT_BROWSER_DEVTOOLS_DEVTOOLS_MANAGER_H_
 
 #include <map>
-#include <set>
 #include <string>
 #include <vector>
 
-#include "base/cancelable_callback.h"
 #include "base/compiler_specific.h"
 #include "base/memory/singleton.h"
-#include "base/observer_list.h"
-#include "content/common/content_export.h"
-#include "content/public/browser/devtools_manager_delegate.h"
 
 namespace content {
 
-class DevToolsAgentHost;
-class RenderViewHost;
-class WebContents;
+class DevToolsManagerDelegate;
 
 // This class is a singleton that manage global DevTools state for the whole
 // browser.
-class CONTENT_EXPORT DevToolsManager {
+class DevToolsManager {
  public:
-  class Observer {
-   public:
-    virtual ~Observer() {}
-
-    typedef DevToolsManagerDelegate::TargetList TargetList;
-
-    // Called when any target information changed.
-    virtual void TargetListChanged(const TargetList& targets) {}
-  };
-
   // Returns single instance of this class. The instance is destroyed on the
   // browser main loop exit so this method MUST NOT be called after that point.
   static DevToolsManager* GetInstance();
@@ -45,30 +28,14 @@
   virtual ~DevToolsManager();
 
   DevToolsManagerDelegate* delegate() const { return delegate_.get(); }
-
-  void AddObserver(Observer* observer);
-  void RemoveObserver(Observer* observer);
-
-  void RenderViewCreated(WebContents* web_contents, RenderViewHost* rvh);
-  void AgentHostChanged(scoped_refptr<DevToolsAgentHost> agent_host);
-
-  static void SetObserverThrottleIntervalForTest(base::TimeDelta interval);
+  void OnClientAttached();
+  void OnClientDetached();
 
  private:
   friend struct DefaultSingletonTraits<DevToolsManager>;
 
-  void UpdateTargetList();
-  void UpdateTargetListThrottled();
-  void NotifyTargetListChanged(const Observer::TargetList& targets);
-
   scoped_ptr<DevToolsManagerDelegate> delegate_;
-  ObserverList<Observer> observer_list_;
-  std::set<DevToolsAgentHost*> attached_hosts_;
-  bool update_target_list_required_;
-  bool update_target_list_scheduled_;
-  base::CancelableClosure update_target_list_callback_;
-
-  static base::TimeDelta observer_throttle_interval_;
+  int client_count_;
 
   DISALLOW_COPY_AND_ASSIGN(DevToolsManager);
 };