Remove prefixed EME.

content/child/simple_webmimeregistry_impl.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/child/simple_webmimeregistry_impl.h"
 
 #include "base/files/file_path.h"
 #include "base/strings/string_util.h"
 #include "base/strings/sys_string_conversions.h"
 #include "base/strings/utf_string_conversions.h"
@@ skipping 45 matching lines @@
     const WebString& mime_type) {
   return mime_util::IsSupportedJavascriptMimeType(ToASCIIOrEmpty(mime_type))
              ? WebMimeRegistry::IsSupported
              : WebMimeRegistry::IsNotSupported;
 }
 
 // When debugging layout tests failures in the test shell,
 // see TestShellWebMimeRegistryImpl.
 WebMimeRegistry::SupportsType SimpleWebMimeRegistryImpl::supportsMediaMIMEType(
     const WebString& mime_type,
-    const WebString& codecs,
-    const WebString& key_system) {
+    const WebString& codecs) {
   // Media features are only supported at the content/renderer/ layer.
   return IsNotSupported;
 }
 
 bool SimpleWebMimeRegistryImpl::supportsMediaSourceMIMEType(
     const WebString& mime_type,
     const WebString& codecs) {
   // Media features are only supported at the content/renderer layer.
   return false;
 }
@@ skipping 16 matching lines @@
 
 WebString SimpleWebMimeRegistryImpl::wellKnownMimeTypeForExtension(
     const WebString& file_extension) {
   std::string mime_type;
   net::GetWellKnownMimeTypeFromExtension(
       blink::WebStringToFilePath(file_extension).value(), &mime_type);
   return WebString::fromUTF8(mime_type);
 }
 
 }  // namespace content