Update string for content protection dialog on Chrome OS

This is being changed at the request of privacy/legal to indicate
'uniquely identify' rather than just 'identify'.

BUG=1146646
TEST=Verified new string in UI

Change-Id: If7716b327da1e6c16e9863f88ddca6f5f8768d96
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2629908
Commit-Queue: Jeffrey Kardatzke <jkardatzke@google.com>
Commit-Queue: Xiaohan Wang <xhwang@chromium.org>
Auto-Submit: Jeffrey Kardatzke <jkardatzke@google.com>
Reviewed-by: Xiaohan Wang <xhwang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#843762}

chrome/app/chromeos_strings.grdp

@@ -3052,7 +3052,7 @@
 
   <!-- 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 to identify your device so it can play the highest quality protected video and audio.
+    <ph name="DOMAIN">$1<ex>example.com</ex></ph> wants to uniquely identify your device so it can play the highest quality protected video and audio.
   </message>
 
   <!-- Network portal notification -->

chrome/app/chromeos_strings_grdp/IDS_PLATFORM_VERIFICATION_DIALOG_HEADLINE.png.sha1

-54bdbaf785801685067b449ddca9515557b00bb9
\ No newline at end of file
+5849d91f21976f0f7899c636fe6a597d251bf0b0
\ No newline at end of file