| Index: Source/core/html/track/TextTrackCue.cpp | 
| diff --git a/Source/core/html/track/TextTrackCue.cpp b/Source/core/html/track/TextTrackCue.cpp | 
| index 1625698eb2845b6a46e0be76298895577049856c..6648b225d356206781ac4d5836f6514693ef04a9 100644 | 
| --- a/Source/core/html/track/TextTrackCue.cpp | 
| +++ b/Source/core/html/track/TextTrackCue.cpp | 
| @@ -92,7 +92,7 @@ static const String& verticalGrowingRightKeyword() | 
|  | 
| // ---------------------------- | 
|  | 
| -TextTrackCueBox::TextTrackCueBox(Document* document, TextTrackCue* cue) | 
| +TextTrackCueBox::TextTrackCueBox(Document& document, TextTrackCue* cue) | 
| : HTMLDivElement(divTag, document) | 
| , m_cue(cue) | 
| { | 
| @@ -204,7 +204,7 @@ TextTrackCue::TextTrackCue(ScriptExecutionContext* context, double start, double | 
| , m_isActive(false) | 
| , m_pauseOnExit(false) | 
| , m_snapToLines(true) | 
| -    , m_cueBackgroundBox(HTMLDivElement::create(toDocument(context))) | 
| +    , m_cueBackgroundBox(HTMLDivElement::create(*toDocument(context))) | 
| , m_displayTreeShouldChange(true) | 
| , m_displayDirection(CSSValueLtr) | 
| { | 
| @@ -228,7 +228,8 @@ TextTrackCue::~TextTrackCue() | 
|  | 
| PassRefPtr<TextTrackCueBox> TextTrackCue::createDisplayTree() | 
| { | 
| -    return TextTrackCueBox::create(ownerDocument(), this); | 
| +    ASSERT(ownerDocument()); | 
| +    return TextTrackCueBox::create(*ownerDocument(), this); | 
| } | 
|  | 
| PassRefPtr<TextTrackCueBox> TextTrackCue::displayTreeInternal() | 
|  |