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

content/browser/devtools/devtools_manager.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/browser/devtools/devtools_manager.h"
 
 #include "base/bind.h"
 #include "base/message_loop/message_loop.h"
-#include "content/browser/devtools/devtools_agent_host_impl.h"
 #include "content/browser/devtools/devtools_netlog_observer.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/content_browser_client.h"
+#include "content/public/browser/devtools_manager_delegate.h"
 
 namespace content {
 
 // static
 DevToolsManager* DevToolsManager::GetInstance() {
   return Singleton<DevToolsManager>::get();
 }
 
 DevToolsManager::DevToolsManager()
     : delegate_(GetContentClient()->browser()->GetDevToolsManagerDelegate()),
-      update_target_list_required_(false),
-      update_target_list_scheduled_(false),
-      update_target_list_callback_(base::Bind(
-          &DevToolsManager::UpdateTargetListThrottled,
-          base::Unretained(this))) {
+      client_count_(0) {
 }
 
 DevToolsManager::~DevToolsManager() {
-  DCHECK(!attached_hosts_.size());
-  update_target_list_callback_.Cancel();
+  DCHECK(!client_count_);
 }
 
-void DevToolsManager::RenderViewCreated(
-    WebContents* web_contents, RenderViewHost* rvh) {
-  if (observer_list_.might_have_observers()) {
-    // Force agent host creation.
-    DevToolsAgentHost::GetOrCreateFor(web_contents);
+void DevToolsManager::OnClientAttached() {
+  if (!client_count_) {
+    BrowserThread::PostTask(
+        BrowserThread::IO,
+        FROM_HERE,
+        base::Bind(&DevToolsNetLogObserver::Attach));
+  }
+  client_count_++;
+}
+
+void DevToolsManager::OnClientDetached() {
+  client_count_--;
+  if (!client_count_) {
+    BrowserThread::PostTask(
+        BrowserThread::IO,
+        FROM_HERE,
+        base::Bind(&DevToolsNetLogObserver::Detach));
   }
 }
 
-void DevToolsManager::AgentHostChanged(
-    scoped_refptr<DevToolsAgentHost> agent_host) {
-  bool was_attached =
-      attached_hosts_.find(agent_host.get()) != attached_hosts_.end();
-  if (agent_host->IsAttached() && !was_attached) {
-    if (!attached_hosts_.size()) {
-      BrowserThread::PostTask(
-          BrowserThread::IO,
-          FROM_HERE,
-          base::Bind(&DevToolsNetLogObserver::Attach));
-    }
-    attached_hosts_.insert(agent_host.get());
-  } else if (!agent_host->IsAttached() && was_attached) {
-    attached_hosts_.erase(agent_host.get());
-    if (!attached_hosts_.size()) {
-      BrowserThread::PostTask(
-          BrowserThread::IO,
-          FROM_HERE,
-          base::Bind(&DevToolsNetLogObserver::Detach));
-    }
-  }
-
-  UpdateTargetList();
-}
-
-void DevToolsManager::AddObserver(Observer* observer) {
-  observer_list_.AddObserver(observer);
-  UpdateTargetList();
-}
-
-void DevToolsManager::RemoveObserver(Observer* observer) {
-  observer_list_.RemoveObserver(observer);
-}
-
-void DevToolsManager::UpdateTargetList() {
-  if (!observer_list_.might_have_observers())
-    return;
-
-  update_target_list_required_ = true;
-  if (!update_target_list_scheduled_)
-    UpdateTargetListThrottled();
-}
-
-void DevToolsManager::UpdateTargetListThrottled() {
-  if (!update_target_list_required_) {
-    update_target_list_scheduled_ = false;
-    return;
-  }
-
-  update_target_list_scheduled_ = true;
-  base::MessageLoop::current()->PostDelayedTask(
-      FROM_HERE,
-      update_target_list_callback_.callback(),
-      observer_throttle_interval_);
-
-  update_target_list_required_ = false;
-  if (!delegate_) {
-    Observer::TargetList empty_list;
-    NotifyTargetListChanged(empty_list);
-    return;
-  }
-  delegate_->EnumerateTargets(base::Bind(
-      &DevToolsManager::NotifyTargetListChanged,
-      base::Unretained(this)));
-}
-
-void DevToolsManager::NotifyTargetListChanged(
-    const Observer::TargetList& targets) {
-  FOR_EACH_OBSERVER(Observer, observer_list_, TargetListChanged(targets));
-}
-
-// static
-base::TimeDelta DevToolsManager::observer_throttle_interval_ =
-    base::TimeDelta::FromMilliseconds(500);
-
-// static
-void DevToolsManager::SetObserverThrottleIntervalForTest(
-    base::TimeDelta interval) {
-  observer_throttle_interval_ = interval;
-}
-
 }  // namespace content