New Task Manager - Phase 1.3.2.B: Implement Tab Contents Task Providing (Prerender)

chrome/browser/task_management/providers/web_contents/web_contents_task_provider.cc

Index: chrome/browser/task_management/providers/web_contents/web_contents_task_provider.cc
diff --git a/chrome/browser/task_management/providers/web_contents/web_contents_task_provider.cc b/chrome/browser/task_management/providers/web_contents/web_contents_task_provider.cc
index 7cd7c0d624ced81be3d0ff6f67599c1e073b736c..4c2493141b6e598ca9a335917c2642549345bfa7 100644
--- a/chrome/browser/task_management/providers/web_contents/web_contents_task_provider.cc
+++ b/chrome/browser/task_management/providers/web_contents/web_contents_task_provider.cc
@@ -35,6 +35,10 @@ class WebContentsEntry : public content::WebContentsObserver {
   // entry's WebContents.
   void CreateAllTasks();
 
+  // Clears all the tasks in this entry. The provider's observer will be
+  // notified if |notify_observer| is true.
+  void ClearAllTasks(bool notify_observer);
+
   // Returns the |RendererTask| that corresponds to the given
   // |render_frame_host| or |nullptr| if the given frame is not tracked by this
   // entry.
@@ -61,10 +65,6 @@ class WebContentsEntry : public content::WebContentsObserver {
   // notifies the provider's observer of the tasks removal.
   void ClearTaskForFrame(RenderFrameHost* render_frame_host);
 
-  // Clears all the tasks in this entry. The provider's observer will be
-  // notified if |notify_observer| is true.
-  void ClearAllTasks(bool notify_observer);
-
   // The provider that owns this entry.
   WebContentsTaskProvider* provider_;
 
@@ -106,6 +106,21 @@ void WebContentsEntry::CreateAllTasks() {
                                           base::Unretained(this)));
 }
 
+void WebContentsEntry::ClearAllTasks(bool notify_observer) {
+  for (auto& pair : frames_by_site_instance_) {
+    FramesList& frames_list = pair.second;
+    DCHECK(!frames_list.empty());
+    RendererTask* task = tasks_by_frames_[frames_list[0]];
+    if (notify_observer)
+      provider_->NotifyObserverTaskRemoved(task);
+    delete task;
+  }
+
+  frames_by_site_instance_.clear();
+  tasks_by_frames_.clear();
+  main_frame_site_instance_ = nullptr;
+}
+
 RendererTask* WebContentsEntry::GetTaskForFrame(
     RenderFrameHost* render_frame_host) const {
   auto itr = tasks_by_frames_.find(render_frame_host);
@@ -238,21 +253,6 @@ void WebContentsEntry::ClearTaskForFrame(RenderFrameHost* render_frame_host) {
   }
 }
 
-void WebContentsEntry::ClearAllTasks(bool notify_observer) {
-  for (auto& pair : frames_by_site_instance_) {
-    FramesList& frames_list = pair.second;
-    DCHECK(!frames_list.empty());
-    RendererTask* task = tasks_by_frames_[frames_list[0]];
-    if (notify_observer)
-      provider_->NotifyObserverTaskRemoved(task);
-    delete task;
-  }
-
-  frames_by_site_instance_.clear();
-  tasks_by_frames_.clear();
-  main_frame_site_instance_ = nullptr;
-}
-
 ////////////////////////////////////////////////////////////////////////////////
 
 WebContentsTaskProvider::WebContentsTaskProvider() : entries_map_() {
@@ -262,7 +262,8 @@ WebContentsTaskProvider::~WebContentsTaskProvider() {
   STLDeleteValues(&entries_map_);
 }
 
-void WebContentsTaskProvider::OnWebContentsTagCreated(WebContentsTag* tag) {
+void WebContentsTaskProvider::OnWebContentsTagCreated(
+    const WebContentsTag* tag) {
   DCHECK(tag);
   content::WebContents* web_contents = tag->web_contents();
   DCHECK(web_contents);
@@ -282,6 +283,22 @@ void WebContentsTaskProvider::OnWebContentsTagCreated(WebContentsTag* tag) {
   entry->CreateAllTasks();
 }
 
+void WebContentsTaskProvider::OnWebContentsTagRemoved(
+    const WebContentsTag* tag) {
+  DCHECK(tag);
+  content::WebContents* web_contents = tag->web_contents();
+  DCHECK(web_contents);
+
+  auto itr = entries_map_.find(web_contents);
+  DCHECK(itr != entries_map_.end());
+  WebContentsEntry* entry = itr->second;
+
+  // Must manually clear the tasks and notify the observer.
+  entry->ClearAllTasks(true);
+  entries_map_.erase(itr);
+  delete entry;
+}
+
 Task* WebContentsTaskProvider::GetTaskOfUrlRequest(int origin_pid,
                                                    int child_id,
                                                    int route_id) {