Use "protected" instead of "premium" for media content.

chrome/app/chromeos_strings.grdp

 <?xml version="1.0" encoding="utf-8"?>
 <!-- Chrome OS-specific strings (included from generated_resources.grd).
      Everything in this file is wrapped in <if expr="chromeos">. -->
 <grit-part>
   <message name="IDS_EMPTY_STRING" desc="Empty string, exist only to make code generic. No translation required.">
   </message>
   <!-- Idle logout dialog for retail mode -->
   <message name="IDS_IDLE_LOGOUT_TITLE" desc="Dialog title for the idle logout dialog. Used in retail mode only.">
     Are you still there?
   </message>
@@ skipping 5774 matching lines @@
   </message>
   <message name="IDS_FILEMANAGER_APP_NAME" desc="Name for the File Manager app.">
     Files
   </message>
   <message name="IDS_FILEMANAGER_APP_DESCRIPTION" desc="Description for the File Manager app.">
     The Files app provides quick access to files that you've saved on Google Drive, external storage, or your Chrome OS device.
   </message>
 
   <!-- Platform verification UI -->
   <message name="IDS_PLATFORM_VERIFICATION_DIALOG_HEADLINE" desc="The label to describe what the dialog wants to confirm.">
-    <ph name="DOMAIN">$1<ex>example.com</ex></ph> wants your device's identity to be verified, by Google, to determine eligibility for enhanced playback of protected media. <ph name="LEARN_MORE">$2<ex>Learn more</ex></ph>.
+    <ph name="DOMAIN">$1<ex>example.com</ex></ph> wants your device's identity to be verified, by Google, to determine eligibility for enhanced playback of protected content. <ph name="LEARN_MORE">$2<ex>Learn more</ex></ph>.
   </message>
 
   <!-- Multi-profiles mode -->
   <message name="IDS_MULTIPROFILES_INTRO_HEADLINE" desc="Describes which feature multi-profiles intro dialog presents.">
     Multiple sign-in
   </message>
   <message name="IDS_MULTIPROFILES_INTRO_MESSAGE" desc="Content of the multi-profiles intro dialog shown when the user adds another user in multi-profiles mode.">
     This feature allows you to quickly access any signed-in user without requiring a password.
 
 Only use this feature with accounts you trust.
@@ skipping 889 matching lines @@
     Attempts left: $1
   </message>
   <message name="IDS_REQUEST_PIN_DIALOG_PIN" desc="The Provider Identification Number abbreviation">
     PIN
   </message>
   <message name="IDS_REQUEST_PIN_DIALOG_PUK" desc="The Personal Unlocking Key (as used in mobile phones) abbreviation">
     PUK
   </message>
 
 </grit-part>