Remove prefixed EME.

content/renderer/renderer_blink_platform_impl.cc

Index: content/renderer/renderer_blink_platform_impl.cc
diff --git a/content/renderer/renderer_blink_platform_impl.cc b/content/renderer/renderer_blink_platform_impl.cc
index 27965a71fe39b3b8ccd29d86b1bd10fc26580ac5..8762537900453744e69801157f0bee987d12c213 100644
--- a/content/renderer/renderer_blink_platform_impl.cc
+++ b/content/renderer/renderer_blink_platform_impl.cc
@@ -457,26 +457,8 @@ RendererBlinkPlatformImpl::MimeRegistry::supportsMediaMIMEType(
     const WebString& key_system) {
   const std::string mime_type_ascii = ToASCIIOrEmpty(mime_type);
 
-  if (!key_system.isEmpty()) {
-    // Check whether the key system is supported with the mime_type and codecs.
-
-    // Chromium only supports ASCII parameters.
-    if (!base::IsStringASCII(key_system))
-      return IsNotSupported;
-
-    std::string key_system_ascii =
-        media::GetUnprefixedKeySystemName(base::UTF16ToASCII(
-            base::StringPiece16(key_system)));
-    std::vector<std::string> codec_vector;
-    media::ParseCodecString(ToASCIIOrEmpty(codecs), &codec_vector, true);
-
-    if (!media::PrefixedIsSupportedKeySystemWithMediaMimeType(
-            mime_type_ascii, codec_vector, key_system_ascii)) {
-      return IsNotSupported;
-    }
-
-    // Continue processing the mime_type and codecs.
-  }
+  // TODO(ddorwin): Remove reference |key_system|. https://crbug.com/249976.
+  DCHECK(key_system.isEmpty());
 
   std::vector<std::string> codec_vector;
   media::ParseCodecString(ToASCIIOrEmpty(codecs), &codec_vector, false);