Update milestone for EME non-standard functionality

third_party/WebKit/Source/core/frame/Deprecation.cpp

 // Copyright 2016 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 "core/frame/Deprecation.h"
 
 #include "core/dom/Document.h"
 #include "core/dom/ExecutionContext.h"
 #include "core/frame/FrameConsole.h"
 #include "core/frame/FrameHost.h"
@@ skipping 375 matching lines @@
 
     case UseCounter::HTMLKeygenElement:
       return willBeRemoved("The <keygen> element", M57, "5716060992962560");
 
     case UseCounter::EncryptedMediaAllSelectedContentTypesMissingCodecs:
       return String::format(
           "EME requires that contentType strings accepted by "
           "requestMediaKeySystemAccess() include codecs. Non-standard support "
           "for contentType strings without codecs will be removed in %s. "
           "Please specify the desired codec(s) as part of the contentType.",
-          milestoneString(M56));
+          milestoneString(M58));
 
     case UseCounter::VRDeprecatedFieldOfView:
       return replacedBy("VREyeParameters.fieldOfView",
                         "projection matrices provided by VRFrameData");
 
     case UseCounter::VRDeprecatedGetPose:
       return replacedBy("VRDisplay.getPose()", "VRDisplay.getFrameData()");
 
     case UseCounter::HTMLEmbedElementLegacyCall:
       return willBeRemoved("HTMLEmbedElement legacy caller", M58,
                            "5715026367217664");
 
     case UseCounter::HTMLObjectElementLegacyCall:
       return willBeRemoved("HTMLObjectElement legacy caller", M58,
                            "5715026367217664");
 
     // Features that aren't deprecated don't have a deprecation message.
     default:
       return String();
   }
 }
 
 }  // namespace blink