EME: Address TODOs related to the removal of prefixed EME

chrome/browser/chromeos/attestation/platform_verification_flow.cc

 // Copyright 2013 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 "chrome/browser/chromeos/attestation/platform_verification_flow.h"
 
 #include <utility>
 
 #include "base/command_line.h"
 #include "base/logging.h"
@@ skipping 182 matching lines @@
     const std::string& challenge,
     const ChallengeCallback& callback) {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
 
   if (!delegate_->GetURL(web_contents).is_valid()) {
     LOG(WARNING) << "PlatformVerificationFlow: Invalid URL.";
     ReportError(callback, INTERNAL_ERROR);
     return;
   }
 
-  // Note: The following two checks are also checked in GetPermissionStatus.
-  // Checking them here explicitly to report the correct error type.
+  // Note: The following checks are performed when use of the protected media
+  // identifier is indicated. The first two in GetPermissionStatus and the third
+  // in DecidePermission.
+  // In Chrome, the result of the first and third could have changed in the
+  // interim, but the mode cannot change.
+  // TODO(ddorwin): Share more code for the first two checks with
+  // ProtectedMediaIdentifierPermissionContext::
+  // IsProtectedMediaIdentifierEnabled().
 
   if (!IsAttestationAllowedByPolicy()) {
     VLOG(1) << "Platform verification not allowed by device policy.";
     ReportError(callback, POLICY_REJECTED);
     return;
   }
 
-  // TODO(xhwang): Change to DCHECK when prefixed EME support is removed.
-  // See http://crbug.com/249976
   if (!delegate_->IsInSupportedMode(web_contents)) {
-    VLOG(1) << "Platform verification denied because it's not supported in the "
-            << "current mode.";
+    NOTREACHED() << "Platform verification not supported in the current mode.";
     ReportError(callback, PLATFORM_NOT_VERIFIED);
     return;
   }
 
   if (!delegate_->IsPermittedByUser(web_contents)) {
     VLOG(1) << "Platform verification not permitted by user.";
     ReportError(callback, USER_REJECTED);
     return;
   }
 
@@ skipping 198 matching lines @@
   if (!operation_success) {
     LOG(WARNING) << "PlatformVerificationFlow: Failed to renew platform "
                     "certificate.";
     return;
   }
   VLOG(1) << "Certificate successfully renewed.";
 }
 
 }  // namespace attestation
 }  // namespace chromeos