Fix memory leak in MediaLog.

tools/heapcheck/suppressions.txt

 # There are three kinds of suppressions in this file.
 # 1. third party stuff we have no control over
 #
 # 2. intentional unit test errors, or stuff that is somehow a false positive
 # in our own code, or stuff that is so trivial it's not worth fixing
 #
 # 3. Suppressions for real chromium bugs that are not yet fixed.
 # These should all be in chromium's bug tracking system (but a few aren't yet).
 # Periodically we should sweep this file and the bug tracker clean by
 # running overnight and removing outdated bugs/suppressions.
@@ skipping 1909 matching lines @@
    fun:BrowserAccessibilityManagerTest_TestCreateEmptyDocument_Test::TestBody
 }
 {
    bug_91845_c
    Heapcheck:Leak
    ...
    fun:BrowserAccessibilityManager::Create
    fun:BrowserAccessibilityManager::CreateEmptyDocument
    fun:BrowserAccessibilityManagerTest_TestCreateEmptyDocument_Test::TestBody
 }
-{
-   bug_91896_a
-   Heapcheck:Leak
-   fun:media::MediaLog::CreateEvent
-   fun:media::MediaLog::AddEventOfType
-   fun:webkit_glue::WebMediaPlayerImpl::play
-   fun:WebKit::WebMediaPlayerClientImpl::play
-   fun:WebCore::MediaPlayer::play
-   fun:WebCore::HTMLMediaElement::updatePlayState
-   fun:WebCore::HTMLMediaElement::setReadyState
-   fun:WebCore::HTMLMediaElement::mediaPlayerReadyStateChanged
-   fun:WebCore::MediaPlayer::readyStateChanged
-   fun:WebKit::WebMediaPlayerClientImpl::readyStateChanged
-   fun:webkit_glue::WebMediaPlayerImpl::SetReadyState
-   fun:webkit_glue::WebMediaPlayerImpl::OnPipelineInitialize
-   fun:webkit_glue::WebMediaPlayerImpl::Proxy::PipelineInitializationTask
-   ...
-   fun:MediaLeakTest_VideoBear_Test::TestBody
-}
-{
-   bug_91896_b
-   Heapcheck:Leak
-   fun:media::MediaLog::CreateEvent
-   fun:media::MediaLog::AddEventOfType
-   fun:webkit_glue::WebMediaPlayerImpl::~WebMediaPlayerImpl
-   fun:WTF::deleteOwnedPtr
-   fun:WTF::OwnPtr::~OwnPtr
-   fun:WebKit::WebMediaPlayerClientImpl::~WebMediaPlayerClientImpl
-   fun:WTF::deleteOwnedPtr
-   fun:WTF::OwnPtr::~OwnPtr
-   fun:WebCore::MediaPlayer::~MediaPlayer
-   fun:WTF::deleteOwnedPtr
-   fun:WTF::OwnPtr::~OwnPtr
-   fun:WebCore::HTMLMediaElement::~HTMLMediaElement
-   fun:WebCore::HTMLVideoElement::~HTMLVideoElement
-   fun:WebCore::TreeShared::removedLastRef
-   fun:WebCore::TreeShared::deref
-   fun:WebCore::Node::derefEventTarget
-   fun:WebCore::EventTarget::deref
-   fun:WTF::derefIfNotNull
-   fun:WTF::RefPtr::~RefPtr
-   fun:WebCore::Event::~Event
-   fun:WTF::RefCounted::deref
-   fun:WebCore::V8Event::derefObject
-   fun:WebCore::WrapperTypeInfo::derefObject
-   fun:WebCore::DOMData::derefObject
-   fun:WebCore::DOMData::handleWeakObject
-   fun:WebCore::DOMDataStore::weakDOMObjectCallback
-   fun:v8::internal::GlobalHandles::Node::PostGarbageCollectionProcessing
-   fun:v8::internal::GlobalHandles::PostGarbageCollectionProcessing
-   fun:v8::internal::Heap::PerformGarbageCollection
-   fun:v8::internal::Heap::CollectGarbage
-   fun:v8::internal::Heap::CollectGarbage
-   fun:v8::internal::Heap::CollectAllGarbage
-}
-{
-   bug_91896_c
-   Heapcheck:Leak
-   fun:media::MediaLog::CreateEvent
-   fun:media::MediaLog::AddEventOfType
-   fun:webkit_glue::WebMediaPlayerImpl::pause
-   fun:WebKit::WebMediaPlayerClientImpl::pause
-   fun:WebCore::MediaPlayer::pause
-   fun:WebCore::HTMLMediaElement::updatePlayState
-   fun:WebCore::HTMLMediaElement::mediaPlayerTimeChanged
-   fun:WebCore::MediaPlayer::timeChanged
-   fun:WebKit::WebMediaPlayerClientImpl::timeChanged
-   fun:webkit_glue::WebMediaPlayerImpl::OnPipelineEnded
-   fun:webkit_glue::WebMediaPlayerImpl::Proxy::PipelineEndedTask
-   ...
-   fun:MediaLeakTest_VideoBear_Test::TestBody
-}