Bug 1269260 - Treat 'iso?' file as MP4 video. r=jya

MozReview-Commit-ID: B4v8LNd479i

--HG--
extra : rebase_source : fed0c7620a1a310c4ec0bd38c48f2da165fb65c9

toolkit/components/mediasniffer/nsMediaSniffer.cpp

@@ -44,6 +44,7 @@ nsMediaSnifferEntry sFtypEntries[] = {
   PATTERN_ENTRY("\xFF\xFF\xFF\xFF", "M4A ", AUDIO_MP4),
   PATTERN_ENTRY("\xFF\xFF\xFF\xFF", "M4P ", AUDIO_MP4),
   PATTERN_ENTRY("\xFF\xFF\xFF\xFF", "qt  ", VIDEO_QUICKTIME),
+  PATTERN_ENTRY("\xFF\xFF\xFF", "iso", VIDEO_MP4), // Could be isom or iso2.
 };
 
 static bool MatchesBrands(const uint8_t aData[4], nsACString& aSniffedType)