Revert "Extract ContextLifecycleNotifier from ScriptExecutionContext."

Source/core/dom/ScriptExecutionContext.cpp

Index: Source/core/dom/ScriptExecutionContext.cpp
diff --git a/Source/core/dom/ScriptExecutionContext.cpp b/Source/core/dom/ScriptExecutionContext.cpp
index f0128f58406ad670e6d75e083851523d2355ee94..2f621cd99d155f96ea0a4a61b6f8fab5c8c5b3f6 100644
--- a/Source/core/dom/ScriptExecutionContext.cpp
+++ b/Source/core/dom/ScriptExecutionContext.cpp
@@ -28,7 +28,6 @@
 #include "config.h"
 #include "core/dom/ScriptExecutionContext.h"
 
-#include "core/dom/ContextLifecycleNotifier.h"
 #include "core/dom/ErrorEvent.h"
 #include "core/dom/EventTarget.h"
 #include "core/dom/MessagePort.h"
@@ -88,7 +87,9 @@ void ScriptExecutionContext::AddConsoleMessageTask::performTask(ScriptExecutionC
 }
 
 ScriptExecutionContext::ScriptExecutionContext()
-    : m_circularSequentialID(0)
+    : m_iteratingActiveDOMObjects(false)
+    , m_inDestructor(false)
+    , m_circularSequentialID(0)
     , m_inDispatchErrorEvent(false)
     , m_activeDOMObjectsAreSuspended(false)
     , m_reasonForSuspendingActiveDOMObjects(static_cast<ActiveDOMObject::ReasonForSuspension>(-1))
@@ -98,6 +99,14 @@ ScriptExecutionContext::ScriptExecutionContext()
 
 ScriptExecutionContext::~ScriptExecutionContext()
 {
+    m_inDestructor = true;
+    for (HashSet<ContextDestructionObserver*>::iterator iter = m_destructionObservers.begin(); iter != m_destructionObservers.end(); iter = m_destructionObservers.begin()) {
+        ContextDestructionObserver* observer = *iter;
+        m_destructionObservers.remove(observer);
+        ASSERT(observer->scriptExecutionContext() == this);
+        observer->contextDestroyed();
+    }
+
     HashSet<MessagePort*>::iterator messagePortsEnd = m_messagePorts.end();
     for (HashSet<MessagePort*>::iterator iter = m_messagePorts.begin(); iter != messagePortsEnd; ++iter) {
         ASSERT((*iter)->scriptExecutionContext() == this);
@@ -148,26 +157,32 @@ void ScriptExecutionContext::destroyedMessagePort(MessagePort* port)
 
 bool ScriptExecutionContext::canSuspendActiveDOMObjects()
 {
-    return lifecycleNotifier()->canSuspendActiveDOMObjects();
-}
-
-bool ScriptExecutionContext::hasPendingActivity()
-{
-    if (lifecycleNotifier()->hasPendingActivity())
-        return true;
-
-    HashSet<MessagePort*>::const_iterator messagePortsEnd = m_messagePorts.end();
-    for (HashSet<MessagePort*>::const_iterator iter = m_messagePorts.begin(); iter != messagePortsEnd; ++iter) {
-        if ((*iter)->hasPendingActivity())
-            return true;
+    // No protection against m_activeDOMObjects changing during iteration: canSuspend() shouldn't execute arbitrary JS.
+    m_iteratingActiveDOMObjects = true;
+    ActiveDOMObjectsSet::iterator activeObjectsEnd = m_activeDOMObjects.end();
+    for (ActiveDOMObjectsSet::iterator iter = m_activeDOMObjects.begin(); iter != activeObjectsEnd; ++iter) {
+        ASSERT((*iter)->scriptExecutionContext() == this);
+        ASSERT((*iter)->suspendIfNeededCalled());
+        if (!(*iter)->canSuspend()) {
+            m_iteratingActiveDOMObjects = false;
+            return false;
+        }
     }
-
-    return false;
+    m_iteratingActiveDOMObjects = false;
+    return true;
 }
 
 void ScriptExecutionContext::suspendActiveDOMObjects(ActiveDOMObject::ReasonForSuspension why)
 {
-    lifecycleNotifier()->notifySuspendingActiveDOMObjects(why);
+    // No protection against m_activeDOMObjects changing during iteration: suspend() shouldn't execute arbitrary JS.
+    m_iteratingActiveDOMObjects = true;
+    ActiveDOMObjectsSet::iterator activeObjectsEnd = m_activeDOMObjects.end();
+    for (ActiveDOMObjectsSet::iterator iter = m_activeDOMObjects.begin(); iter != activeObjectsEnd; ++iter) {
+        ASSERT((*iter)->scriptExecutionContext() == this);
+        ASSERT((*iter)->suspendIfNeededCalled());
+        (*iter)->suspend(why);
+    }
+    m_iteratingActiveDOMObjects = false;
     m_activeDOMObjectsAreSuspended = true;
     m_reasonForSuspendingActiveDOMObjects = why;
 }
@@ -175,33 +190,70 @@ void ScriptExecutionContext::suspendActiveDOMObjects(ActiveDOMObject::ReasonForS
 void ScriptExecutionContext::resumeActiveDOMObjects()
 {
     m_activeDOMObjectsAreSuspended = false;
-    lifecycleNotifier()->notifyResumingActiveDOMObjects();
+    // No protection against m_activeDOMObjects changing during iteration: resume() shouldn't execute arbitrary JS.
+    m_iteratingActiveDOMObjects = true;
+    ActiveDOMObjectsSet::iterator activeObjectsEnd = m_activeDOMObjects.end();
+    for (ActiveDOMObjectsSet::iterator iter = m_activeDOMObjects.begin(); iter != activeObjectsEnd; ++iter) {
+        ASSERT((*iter)->scriptExecutionContext() == this);
+        ASSERT((*iter)->suspendIfNeededCalled());
+        (*iter)->resume();
+    }
+    m_iteratingActiveDOMObjects = false;
 }
 
 void ScriptExecutionContext::stopActiveDOMObjects()
 {
     m_activeDOMObjectsAreStopped = true;
-    lifecycleNotifier()->notifyStoppingActiveDOMObjects();
+    // No protection against m_activeDOMObjects changing during iteration: stop() shouldn't execute arbitrary JS.
+    m_iteratingActiveDOMObjects = true;
+    ActiveDOMObjectsSet::iterator activeObjectsEnd = m_activeDOMObjects.end();
+    for (ActiveDOMObjectsSet::iterator iter = m_activeDOMObjects.begin(); iter != activeObjectsEnd; ++iter) {
+        ASSERT((*iter)->scriptExecutionContext() == this);
+        ASSERT((*iter)->suspendIfNeededCalled());
+        (*iter)->stop();
+    }
+    m_iteratingActiveDOMObjects = false;
+
     // Also close MessagePorts. If they were ActiveDOMObjects (they could be) then they could be stopped instead.
     closeMessagePorts();
 }
 
 void ScriptExecutionContext::suspendActiveDOMObjectIfNeeded(ActiveDOMObject* object)
 {
-    ASSERT(lifecycleNotifier()->contains(object));
+    ASSERT(m_activeDOMObjects.contains(object));
     // Ensure all ActiveDOMObjects are suspended also newly created ones.
     if (m_activeDOMObjectsAreSuspended)
         object->suspend(m_reasonForSuspendingActiveDOMObjects);
 }
 
-void ScriptExecutionContext::wasObservedBy(ContextDestructionObserver* observer, ContextDestructionObserver::Type as)
+void ScriptExecutionContext::didCreateActiveDOMObject(ActiveDOMObject* object)
+{
+    ASSERT(object);
+    ASSERT(!m_inDestructor);
+    if (m_iteratingActiveDOMObjects)
+        CRASH();
+    m_activeDOMObjects.add(object);
+}
+
+void ScriptExecutionContext::willDestroyActiveDOMObject(ActiveDOMObject* object)
+{
+    ASSERT(object);
+    if (m_iteratingActiveDOMObjects)
+        CRASH();
+    m_activeDOMObjects.remove(object);
+}
+
+void ScriptExecutionContext::didCreateDestructionObserver(ContextDestructionObserver* observer)
 {
-    lifecycleNotifier()->addObserver(observer, as);
+    ASSERT(observer);
+    ASSERT(!m_inDestructor);
+    m_destructionObservers.add(observer);
 }
 
-void ScriptExecutionContext::wasUnobservedBy(ContextDestructionObserver* observer, ContextDestructionObserver::Type as)
+void ScriptExecutionContext::willDestroyDestructionObserver(ContextDestructionObserver* observer)
 {
-    lifecycleNotifier()->removeObserver(observer, as);
+    ASSERT(observer);
+    m_destructionObservers.remove(observer);
 }
 
 void ScriptExecutionContext::closeMessagePorts() {
@@ -298,27 +350,19 @@ double ScriptExecutionContext::timerAlignmentInterval() const
     return DOMTimer::visiblePageAlignmentInterval();
 }
 
-ContextLifecycleNotifier* ScriptExecutionContext::lifecycleNotifier()
-{
-    if (!m_lifecycleNotifier)
-        m_lifecycleNotifier = const_cast<ScriptExecutionContext*>(this)->createLifecycleNotifier();
-    return m_lifecycleNotifier.get();
-}
-
-PassOwnPtr<ContextLifecycleNotifier> ScriptExecutionContext::createLifecycleNotifier()
-{
-    return ContextLifecycleNotifier::create(this);
-}
-
 void ScriptExecutionContext::reportMemoryUsage(MemoryObjectInfo* memoryObjectInfo) const
 {
     MemoryClassInfo info(memoryObjectInfo, this, WebCoreMemoryTypes::DOM);
     SecurityContext::reportMemoryUsage(memoryObjectInfo);
     info.addMember(m_messagePorts, "messagePorts");
-    info.addMember(m_lifecycleNotifier, "lifecycleObserver");
+    info.addMember(m_destructionObservers, "destructionObservers");
+    info.addMember(m_activeDOMObjects, "activeDOMObjects");
     info.addMember(m_timeouts, "timeouts");
     info.addMember(m_pendingExceptions, "pendingExceptions");
     info.addMember(m_publicURLManager, "publicURLManager");
+    ActiveDOMObjectsSet::iterator activeObjectsEnd = m_activeDOMObjects.end();
+    for (ActiveDOMObjectsSet::iterator iter = m_activeDOMObjects.begin(); iter != activeObjectsEnd; ++iter)
+        info.addMember(*iter, "activeDOMObject", WTF::RetainingPointer);
 }
 
 ScriptExecutionContext::Task::~Task()
@@ -327,6 +371,7 @@ ScriptExecutionContext::Task::~Task()
 
 void ScriptExecutionContext::setDatabaseContext(DatabaseContext* databaseContext)
 {
+    ASSERT(!m_databaseContext);
     m_databaseContext = databaseContext;
 }