| Index: media/base/key_systems.cc
 | 
| diff --git a/media/base/key_systems.cc b/media/base/key_systems.cc
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| index 32fa1c7314fd48b6d57f17fca803f9ce7a5a022e..78029e1dffe8a24dc181eb564a36eeedd330a33c 100644
 | 
| --- a/media/base/key_systems.cc
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| +++ b/media/base/key_systems.cc
 | 
| @@ -674,12 +674,14 @@ EmeConfigRule KeySystemsImpl::GetContentTypeConfigRule(
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|    SupportedCodecs media_type_codec_mask = EME_CODEC_NONE;
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|    switch (media_type) {
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|      case EmeMediaType::AUDIO:
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| -      if (!base::StartsWithASCII(container_mime_type, "audio/", true))
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| +      if (!base::StartsWith(container_mime_type, "audio/",
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| +                            base::CompareCase::SENSITIVE))
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|          return EmeConfigRule::NOT_SUPPORTED;
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|        media_type_codec_mask = audio_codec_mask_;
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|        break;
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|      case EmeMediaType::VIDEO:
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| -      if (!base::StartsWithASCII(container_mime_type, "video/", true))
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| +      if (!base::StartsWith(container_mime_type, "video/",
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| +                            base::CompareCase::SENSITIVE))
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|          return EmeConfigRule::NOT_SUPPORTED;
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|        media_type_codec_mask = video_codec_mask_;
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|        break;
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| 
 |