Revert 200932 "Lower the priority of shared workers that aren't ..."

> Lower the priority of shared workers that aren't associated with the foreground tab.
> 
> This should help out less powerful devices in the case where there's a shared worker in another tab and a cpu intensive page in the foreground.
> 
> BUG=
> TEST=Open a doc, see webworker running, switch tabs and check webworker's priority by outputting contents of /sys/fs/cgroup/cpu/chrome_renderers/background/cgroup.proc on ChromeOS. With an open doc in a background tab, run 720p video (ie. youtube) at fullscreen, should stay fairly smooth.
> 
> Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=199840
> 
> Review URL: https://chromiumcodereview.appspot.com/14137016

TBR=simonhatch@chromium.org

Review URL: https://codereview.chromium.org/15465006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@201090 0039d316-1c4b-4281-b951-d872f2087c98

6 files changed, 3 insertions, 234 deletions

diff --git a/content/browser/browser_child_process_host_impl.cc b/content/browser/browser_child_process_host_impl.cc
index 9851e8c..6a2218f 100644
--- a/content/browser/browser_child_process_host_impl.cc
+++ b/content/browser/browser_child_process_host_impl.cc
@@ -205,10 +205,6 @@ void BrowserChildProcessHostImpl::ForceShutdown() {
   child_process_host_->ForceShutdown();
 }
 
-void BrowserChildProcessHostImpl::SetBackgrounded(bool backgrounded) {
-  child_process_->SetProcessBackgrounded(backgrounded);
-}
-
 void BrowserChildProcessHostImpl::SetTerminateChildOnShutdown(
     bool terminate_on_shutdown) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
diff --git a/content/browser/browser_child_process_host_impl.h b/content/browser/browser_child_process_host_impl.h
index 9933ca3..e3fdcb5 100644
--- a/content/browser/browser_child_process_host_impl.h
+++ b/content/browser/browser_child_process_host_impl.h
@@ -61,9 +61,6 @@ class CONTENT_EXPORT BrowserChildProcessHostImpl
   // Removes this host from the host list. Calls ChildProcessHost::ForceShutdown
   void ForceShutdown();
 
-  // Callers can reduce the BrowserChildProcess' priority.
-  void SetBackgrounded(bool backgrounded);
-
   // Controls whether the child process should be terminated on browser
   // shutdown. Default is to always terminate.
   void SetTerminateChildOnShutdown(bool terminate_on_shutdown);
diff --git a/content/browser/worker_host/worker_process_host.cc b/content/browser/worker_host/worker_process_host.cc
index 27d51e2..b818b9d 100644
--- a/content/browser/worker_host/worker_process_host.cc
+++ b/content/browser/worker_host/worker_process_host.cc
@@ -114,8 +114,7 @@ WorkerProcessHost::WorkerProcessHost(
     ResourceContext* resource_context,
     const WorkerStoragePartition& partition)
     : resource_context_(resource_context),
-      partition_(partition),
-      process_launched_(false) {
+      partition_(partition) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
   DCHECK(resource_context_);
   process_.reset(
@@ -319,9 +318,6 @@ bool WorkerProcessHost::FilterMessage(const IPC::Message& message,
 }
 
 void WorkerProcessHost::OnProcessLaunched() {
-  process_launched_ = true;
-
-  WorkerServiceImpl::GetInstance()->NotifyWorkerProcessCreated();
 }
 
 bool WorkerProcessHost::OnMessageReceived(const IPC::Message& message) {
@@ -542,18 +538,10 @@ void WorkerProcessHost::TerminateWorker(int worker_route_id) {
   Send(new WorkerMsg_TerminateWorkerContext(worker_route_id));
 }
 
-void WorkerProcessHost::SetBackgrounded(bool backgrounded) {
-  process_->SetBackgrounded(backgrounded);
-}
-
 const ChildProcessData& WorkerProcessHost::GetData() {
   return process_->GetData();
 }
 
-bool WorkerProcessHost::process_launched() const {
-  return process_launched_;
-}
-
 std::vector<std::pair<int, int> > WorkerProcessHost::GetRenderViewIDsForWorker(
     int worker_route_id) {
   std::vector<std::pair<int, int> > result;
diff --git a/content/browser/worker_host/worker_process_host.h b/content/browser/worker_host/worker_process_host.h
index 715e38c..dd1d58f 100644
--- a/content/browser/worker_host/worker_process_host.h
+++ b/content/browser/worker_host/worker_process_host.h
@@ -158,9 +158,6 @@ class WorkerProcessHost : public BrowserChildProcessHostDelegate,
   // Terminates the given worker, i.e. based on a UI action.
   CONTENT_EXPORT void TerminateWorker(int worker_route_id);
 
-  // Callers can reduce the WorkerProcess' priority.
-  void SetBackgrounded(bool backgrounded);
-
   CONTENT_EXPORT const ChildProcessData& GetData();
 
   typedef std::list<WorkerInstance> Instances;
@@ -170,8 +167,6 @@ class WorkerProcessHost : public BrowserChildProcessHostDelegate,
     return resource_context_;
   }
 
-  bool process_launched() const;
-
  protected:
   friend class WorkerServiceImpl;
 
@@ -226,7 +221,6 @@ class WorkerProcessHost : public BrowserChildProcessHostDelegate,
   scoped_refptr<WorkerMessageFilter> worker_message_filter_;
 
   scoped_ptr<BrowserChildProcessHostImpl> process_;
-  bool process_launched_;
 
   DISALLOW_COPY_AND_ASSIGN(WorkerProcessHost);
 };
diff --git a/content/browser/worker_host/worker_service_impl.cc b/content/browser/worker_host/worker_service_impl.cc
index 2299500..703b31f 100644
--- a/content/browser/worker_host/worker_service_impl.cc
+++ b/content/browser/worker_host/worker_service_impl.cc
@@ -10,20 +10,12 @@
 #include "base/logging.h"
 #include "base/threading/thread.h"
 #include "content/browser/devtools/worker_devtools_manager.h"
-#include "content/browser/renderer_host/render_widget_host_impl.h"
 #include "content/browser/worker_host/worker_message_filter.h"
 #include "content/browser/worker_host/worker_process_host.h"
 #include "content/common/view_messages.h"
 #include "content/common/worker_messages.h"
 #include "content/public/browser/child_process_data.h"
-#include "content/public/browser/notification_service.h"
-#include "content/public/browser/notification_types.h"
-#include "content/public/browser/render_process_host.h"
-#include "content/public/browser/render_view_host.h"
-#include "content/public/browser/render_widget_host.h"
-#include "content/public/browser/render_widget_host_view.h"
 #include "content/public/browser/resource_context.h"
-#include "content/public/browser/web_contents.h"
 #include "content/public/browser/worker_service_observer.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/common/process_type.h"
@@ -33,192 +25,6 @@ namespace content {
 const int WorkerServiceImpl::kMaxWorkersWhenSeparate = 64;
 const int WorkerServiceImpl::kMaxWorkersPerTabWhenSeparate = 16;
 
-class WorkerPrioritySetter
-    : public NotificationObserver,
-      public base::RefCountedThreadSafe<WorkerPrioritySetter,
-                                        BrowserThread::DeleteOnUIThread> {
- public:
-  WorkerPrioritySetter();
-
-  // Posts a task to the UI thread to register to receive notifications.
-  void Initialize();
-
-  // Invoked by WorkerServiceImpl when a worker process is created.
-  void NotifyWorkerProcessCreated();
-
- private:
-  friend class base::RefCountedThreadSafe<WorkerPrioritySetter>;
-  friend struct BrowserThread::DeleteOnThread<BrowserThread::UI>;
-  friend class base::DeleteHelper<WorkerPrioritySetter>;
-  virtual ~WorkerPrioritySetter();
-
-  // Posts a task to perform a worker priority update.
-  void PostTaskToGatherAndUpdateWorkerPriorities();
-
-  // Gathers up a list of the visible tabs and then updates priorities for
-  // all the shared workers.
-  void GatherVisibleIDsAndUpdateWorkerPriorities();
-
-  // Registers as an observer to receive notifications about
-  // widgets being shown.
-  void RegisterObserver();
-
-  // Sets priorities for shared workers given a set of visible tabs (as a
-  // std::set of std::pair<render_process, render_view> ids.
-  void UpdateWorkerPrioritiesFromVisibleSet(
-      const std::set<std::pair<int, int> >* visible);
-
-  // Called to refresh worker priorities when focus changes between tabs.
-  void OnRenderWidgetVisibilityChanged(std::pair<int, int>);
-
-  // NotificationObserver implementation.
-  virtual void Observe(int type,
-                       const NotificationSource& source,
-                       const NotificationDetails& details) OVERRIDE;
-
-  NotificationRegistrar registrar_;
-};
-
-WorkerPrioritySetter::WorkerPrioritySetter() {
-}
-
-WorkerPrioritySetter::~WorkerPrioritySetter() {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-}
-
-void WorkerPrioritySetter::Initialize() {
-  BrowserThread::PostTask(
-      BrowserThread::UI, FROM_HERE,
-      base::Bind(&WorkerPrioritySetter::RegisterObserver, this));
-}
-
-void WorkerPrioritySetter::NotifyWorkerProcessCreated() {
-  PostTaskToGatherAndUpdateWorkerPriorities();
-}
-
-void WorkerPrioritySetter::PostTaskToGatherAndUpdateWorkerPriorities() {
-  BrowserThread::PostTask(
-      BrowserThread::UI, FROM_HERE,
-      base::Bind(
-          &WorkerPrioritySetter::GatherVisibleIDsAndUpdateWorkerPriorities,
-          this));
-}
-
-void WorkerPrioritySetter::GatherVisibleIDsAndUpdateWorkerPriorities() {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  std::set<std::pair<int, int> >* visible_renderer_ids =
-      new std::set<std::pair<int, int> >();
-
-  // Gather up all the visible renderer process/view pairs
-  for (RenderProcessHost::iterator it =
-       RenderProcessHost::AllHostsIterator();
-       !it.IsAtEnd(); it.Advance()) {
-    RenderProcessHost* render_process_host = it.GetCurrentValue();
-    if (render_process_host->VisibleWidgetCount()) {
-      for (RenderProcessHost::RenderWidgetHostsIterator rit =
-           render_process_host->GetRenderWidgetHostsIterator(); !rit.IsAtEnd();
-           rit.Advance()) {
-        RenderWidgetHost* render_widget =
-            render_process_host->GetRenderWidgetHostByID(rit.GetCurrentKey());
-        if (render_widget) {
-          RenderWidgetHostView* render_view = render_widget->GetView();
-          if (render_view && render_view->IsShowing()) {
-            visible_renderer_ids->insert(
-                std::pair<int, int>(render_process_host->GetID(),
-                                    render_widget->GetRoutingID()));
-          }
-        }
-      }
-    }
-  }
-
-  BrowserThread::PostTask(
-      BrowserThread::IO, FROM_HERE,
-      base::Bind(&WorkerPrioritySetter::UpdateWorkerPrioritiesFromVisibleSet,
-                 this, base::Owned(visible_renderer_ids)));
-}
-
-void WorkerPrioritySetter::UpdateWorkerPrioritiesFromVisibleSet(
-    const std::set<std::pair<int, int> >* visible_renderer_ids) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
-
-  for (WorkerProcessHostIterator iter; !iter.Done(); ++iter) {
-    if (!iter->process_launched())
-      continue;
-    bool throttle = true;
-
-    for (WorkerProcessHost::Instances::const_iterator instance =
-        iter->instances().begin(); instance != iter->instances().end();
-        ++instance) {
-
-      // This code assumes one worker per process
-      WorkerProcessHost::Instances::const_iterator first_instance =
-          iter->instances().begin();
-      if (first_instance == iter->instances().end())
-        continue;
-
-      WorkerDocumentSet::DocumentInfoSet::const_iterator info =
-          first_instance->worker_document_set()->documents().begin();
-
-      for (; info != first_instance->worker_document_set()->documents().end();
-          ++info) {
-        std::pair<int, int> id(
-            info->render_process_id(), info->render_view_id());
-        if (visible_renderer_ids->find(id) != visible_renderer_ids->end()) {
-          throttle = false;
-          break;
-        }
-      }
-
-      if (!throttle ) {
-        break;
-      }
-    }
-
-    iter->SetBackgrounded(throttle);
-  }
-}
-
-void WorkerPrioritySetter::OnRenderWidgetVisibilityChanged(
-    std::pair<int, int> id) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
-  std::set<std::pair<int, int> > visible_renderer_ids;
-
-  visible_renderer_ids.insert(id);
-
-  UpdateWorkerPrioritiesFromVisibleSet(&visible_renderer_ids);
-}
-
-void WorkerPrioritySetter::RegisterObserver() {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  registrar_.Add(this, NOTIFICATION_RENDER_WIDGET_VISIBILITY_CHANGED,
-                 NotificationService::AllBrowserContextsAndSources());
-  registrar_.Add(this, NOTIFICATION_RENDERER_PROCESS_CREATED,
-                 NotificationService::AllBrowserContextsAndSources());
-}
-
-void WorkerPrioritySetter::Observe(int type,
-    const NotificationSource& source, const NotificationDetails& details) {
-  if (type == NOTIFICATION_RENDER_WIDGET_VISIBILITY_CHANGED) {
-    bool visible = *Details<bool>(details).ptr();
-
-    if (visible) {
-      int render_widget_id =
-          Source<RenderWidgetHost>(source).ptr()->GetRoutingID();
-      int render_process_pid =
-          Source<RenderWidgetHost>(source).ptr()->GetProcess()->GetID();
-
-      BrowserThread::PostTask(
-          BrowserThread::IO, FROM_HERE,
-          base::Bind(&WorkerPrioritySetter::OnRenderWidgetVisibilityChanged,
-              this, std::pair<int, int>(render_process_pid, render_widget_id)));
-    }
-  }
-  else if (type == NOTIFICATION_RENDERER_PROCESS_CREATED) {
-    PostTaskToGatherAndUpdateWorkerPriorities();
-  }
-}
-
 WorkerService* WorkerService::GetInstance() {
   return WorkerServiceImpl::GetInstance();
 }
@@ -228,10 +34,7 @@ WorkerServiceImpl* WorkerServiceImpl::GetInstance() {
   return Singleton<WorkerServiceImpl>::get();
 }
 
-WorkerServiceImpl::WorkerServiceImpl()
-    : priority_setter_(new WorkerPrioritySetter()),
-      next_worker_route_id_(0) {
-  priority_setter_->Initialize();
+WorkerServiceImpl::WorkerServiceImpl() : next_worker_route_id_(0) {
 }
 
 WorkerServiceImpl::~WorkerServiceImpl() {
@@ -654,10 +457,6 @@ void WorkerServiceImpl::NotifyWorkerDestroyed(
                     WorkerDestroyed(process->GetData().id, worker_route_id));
 }
 
-void WorkerServiceImpl::NotifyWorkerProcessCreated() {
-  priority_setter_->NotifyWorkerProcessCreated();
-}
-
 WorkerProcessHost::WorkerInstance* WorkerServiceImpl::FindSharedWorkerInstance(
     const GURL& url,
     const string16& name,
diff --git a/content/browser/worker_host/worker_service_impl.h b/content/browser/worker_host/worker_service_impl.h
index aed05b8..845f433 100644
--- a/content/browser/worker_host/worker_service_impl.h
+++ b/content/browser/worker_host/worker_service_impl.h
@@ -11,7 +11,6 @@
 #include "base/observer_list.h"
 #include "base/threading/non_thread_safe.h"
 #include "content/browser/worker_host/worker_process_host.h"
-#include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
 #include "content/public/browser/worker_service.h"
 
@@ -22,7 +21,6 @@ namespace content {
 class ResourceContext;
 class WorkerServiceObserver;
 class WorkerStoragePartition;
-class WorkerPrioritySetter;
 
 class CONTENT_EXPORT WorkerServiceImpl
     : public NON_EXPORTED_BASE(WorkerService) {
@@ -74,8 +72,6 @@ class CONTENT_EXPORT WorkerServiceImpl
       WorkerProcessHost* process,
       int worker_route_id);
 
-  void NotifyWorkerProcessCreated();
-
   // Used when we run each worker in a separate process.
   static const int kMaxWorkersWhenSeparate;
   static const int kMaxWorkersPerTabWhenSeparate;
@@ -126,8 +122,7 @@ class CONTENT_EXPORT WorkerServiceImpl
       const WorkerStoragePartition& worker_partition,
       ResourceContext* resource_context);
 
-  scoped_refptr<WorkerPrioritySetter> priority_setter_;
-
+  NotificationRegistrar registrar_;
   int next_worker_route_id_;
 
   WorkerProcessHost::Instances queued_workers_;