Use a TextTrackLoaderClient reference (not pointer)

Source/core/loader/TextTrackLoader.h

Index: Source/core/loader/TextTrackLoader.h
diff --git a/Source/core/loader/TextTrackLoader.h b/Source/core/loader/TextTrackLoader.h
index 2dd1cb35a35ca161e2bee20b1967a234311e2c9b..451ef79173981b282b28462e4c1a55e9c1a68e6d 100644
--- a/Source/core/loader/TextTrackLoader.h
+++ b/Source/core/loader/TextTrackLoader.h
@@ -52,7 +52,7 @@ class TextTrackLoader : public RawResourceClient, private WebVTTParserClient {
     WTF_MAKE_NONCOPYABLE(TextTrackLoader);
     WTF_MAKE_FAST_ALLOCATED;
 public:
-    static PassOwnPtr<TextTrackLoader> create(TextTrackLoaderClient* client, Document& document)
+    static PassOwnPtr<TextTrackLoader> create(TextTrackLoaderClient& client, Document& document)
     {
         return adoptPtr(new TextTrackLoader(client, document));
     }
@@ -77,12 +77,12 @@ private:
     virtual void newRegionsParsed() OVERRIDE;
     virtual void fileFailedToParse() OVERRIDE;
 
-    TextTrackLoader(TextTrackLoaderClient*, Document&);
+    TextTrackLoader(TextTrackLoaderClient&, Document&);
 
     void cueLoadTimerFired(Timer<TextTrackLoader>*);
     void corsPolicyPreventedLoad();
 
-    TextTrackLoaderClient* m_client;
+    TextTrackLoaderClient& m_client;
     OwnPtr<WebVTTParser> m_cueParser;
     ResourcePtr<RawResource> m_resource;
     // FIXME: Remove this pointer and get the Document from m_client.