1 files changed, 21 insertions, 24 deletions

diff --git a/Source/WebCore/xml/XMLHttpRequestProgressEventThrottle.cpp b/Source/WebCore/xml/XMLHttpRequestProgressEventThrottle.cpp
index 615e515bb..36662656b 100644
--- a/Source/WebCore/xml/XMLHttpRequestProgressEventThrottle.cpp
+++ b/Source/WebCore/xml/XMLHttpRequestProgressEventThrottle.cpp
@@ -27,6 +27,7 @@
 #include "config.h"
 #include "XMLHttpRequestProgressEventThrottle.h"
 
+#include "EventNames.h"
 #include "EventTarget.h"
 #include "XMLHttpRequestProgressEvent.h"
 
@@ -41,7 +42,7 @@ XMLHttpRequestProgressEventThrottle::XMLHttpRequestProgressEventThrottle(EventTa
     , m_loaded(0)
     , m_total(0)
     , m_deferEvents(false)
-    , m_dispatchDeferredEventsTimer(this, &XMLHttpRequestProgressEventThrottle::dispatchDeferredEvents)
+    , m_dispatchDeferredEventsTimer(*this, &XMLHttpRequestProgressEventThrottle::dispatchDeferredEvents)
 {
     ASSERT(target);
 }
@@ -55,6 +56,9 @@ void XMLHttpRequestProgressEventThrottle::dispatchThrottledProgressEvent(bool le
     m_lengthComputable = lengthComputable;
     m_loaded = loaded;
     m_total = total;
+
+    if (!m_target->hasEventListeners(eventNames().progressEvent))
+        return;
     
     if (m_deferEvents) {
         // Only store the latest progress event while suspended.
@@ -63,8 +67,7 @@ void XMLHttpRequestProgressEventThrottle::dispatchThrottledProgressEvent(bool le
     }
 
     if (!isActive()) {
-        // The timer is not active so the least frequent event for now is every byte.
-        // Just go ahead and dispatch the event.
+        // The timer is not active so the least frequent event for now is every byte. Just dispatch the event.
 
         // We should not have any throttled progress event.
         ASSERT(!m_hasThrottledProgressEvent);
@@ -79,7 +82,7 @@ void XMLHttpRequestProgressEventThrottle::dispatchThrottledProgressEvent(bool le
     m_hasThrottledProgressEvent = true;
 }
 
-void XMLHttpRequestProgressEventThrottle::dispatchReadyStateChangeEvent(PassRefPtr<Event> event, ProgressEventAction progressEventAction)
+void XMLHttpRequestProgressEventThrottle::dispatchReadyStateChangeEvent(Event& event, ProgressEventAction progressEventAction)
 {
     if (progressEventAction == FlushProgressEvent)
         flushProgressEvent();
@@ -87,11 +90,10 @@ void XMLHttpRequestProgressEventThrottle::dispatchReadyStateChangeEvent(PassRefP
     dispatchEvent(event);
 }
 
-void XMLHttpRequestProgressEventThrottle::dispatchEvent(PassRefPtr<Event> event)
+void XMLHttpRequestProgressEventThrottle::dispatchEvent(Event& event)
 {
-    ASSERT(event);
     if (m_deferEvents) {
-        if (m_deferredEvents.size() > 1 && event->type() == eventNames().readystatechangeEvent && event->type() == m_deferredEvents.last()->type()) {
+        if (m_deferredEvents.size() > 1 && event.type() == eventNames().readystatechangeEvent && event.type() == m_deferredEvents.last()->type()) {
             // Readystatechange events are state-less so avoid repeating two identical events in a row on resume.
             return;
         }
@@ -100,7 +102,7 @@ void XMLHttpRequestProgressEventThrottle::dispatchEvent(PassRefPtr<Event> event)
         m_target->dispatchEvent(event);
 }
 
-void XMLHttpRequestProgressEventThrottle::dispatchProgressEvent(const AtomicString &type)
+void XMLHttpRequestProgressEventThrottle::dispatchProgressEvent(const AtomicString& type)
 {
     ASSERT(type == eventNames().loadstartEvent || type == eventNames().progressEvent || type == eventNames().loadEvent || type == eventNames().loadendEvent || type == eventNames().abortEvent || type == eventNames().errorEvent || type == eventNames().timeoutEvent);
 
@@ -110,51 +112,46 @@ void XMLHttpRequestProgressEventThrottle::dispatchProgressEvent(const AtomicStri
         m_total = 0;
     }
 
-    dispatchEvent(XMLHttpRequestProgressEvent::create(type, m_lengthComputable, m_loaded, m_total));
+    if (m_target->hasEventListeners(type))
+        dispatchEvent(XMLHttpRequestProgressEvent::create(type, m_lengthComputable, m_loaded, m_total));
 }
 
 void XMLHttpRequestProgressEventThrottle::flushProgressEvent()
 {
     if (m_deferEvents && m_deferredProgressEvent) {
         // Move the progress event to the queue, to get it in the right order on resume.
-        m_deferredEvents.append(m_deferredProgressEvent);
-        m_deferredProgressEvent = 0;
+        m_deferredEvents.append(m_deferredProgressEvent.releaseNonNull());
         return;
     }
 
     if (!hasEventToDispatch())
         return;
-    PassRefPtr<Event> event = XMLHttpRequestProgressEvent::create(eventNames().progressEvent, m_lengthComputable, m_loaded, m_total);
+    Ref<Event> event = XMLHttpRequestProgressEvent::create(eventNames().progressEvent, m_lengthComputable, m_loaded, m_total);
     m_hasThrottledProgressEvent = false;
 
     // We stop the timer as this is called when no more events are supposed to occur.
     stop();
 
-    dispatchEvent(event);
+    dispatchEvent(WTFMove(event));
 }
 
-void XMLHttpRequestProgressEventThrottle::dispatchDeferredEvents(Timer<XMLHttpRequestProgressEventThrottle>* timer)
+void XMLHttpRequestProgressEventThrottle::dispatchDeferredEvents()
 {
-    ASSERT_UNUSED(timer, timer == &m_dispatchDeferredEventsTimer);
     ASSERT(m_deferEvents);
     m_deferEvents = false;
 
     // Take over the deferred events before dispatching them which can potentially add more.
-    Vector<RefPtr<Event>> deferredEvents;
-    m_deferredEvents.swap(deferredEvents);
+    auto deferredEvents = WTFMove(m_deferredEvents);
 
-    RefPtr<Event> deferredProgressEvent = m_deferredProgressEvent;
-    m_deferredProgressEvent = 0;
+    RefPtr<Event> deferredProgressEvent = WTFMove(m_deferredProgressEvent);
 
-    Vector<RefPtr<Event>>::const_iterator it = deferredEvents.begin();
-    const Vector<RefPtr<Event>>::const_iterator end = deferredEvents.end();
-    for (; it != end; ++it)
-        dispatchEvent(*it);
+    for (auto& deferredEvent : deferredEvents)
+        dispatchEvent(deferredEvent);
 
     // The progress event will be in the m_deferredEvents vector if the load was finished while suspended.
     // If not, just send the most up-to-date progress on resume.
     if (deferredProgressEvent)
-        dispatchEvent(deferredProgressEvent);
+        dispatchEvent(*deferredProgressEvent);
 }
 
 void XMLHttpRequestProgressEventThrottle::fired()