Bug 1400829 - Remove trackingProtectionPBM5 string since it is no longer being used anymore. r=flod

MozReview-Commit-ID: 2XAGhjL9AyK

--HG--
extra : rebase_source : c4632eaa6654ac360582f423b7a7f580ba32d9a7

browser/locales/en-US/chrome/browser/preferences/privacy.dtd

@@ -15,10 +15,7 @@
 <!ENTITY  trackingProtectionExceptions.label   "Exceptions…">
 <!ENTITY  trackingProtectionExceptions.accesskey "x">
 
-<!-- LOCALIZATION NOTE (trackingProtectionPBM5.label): This string is displayed if privacy.trackingprotection.ui.enabled is set to true. This currently happens on the release and beta channel. -->
+<!-- LOCALIZATION NOTE (trackingProtectionPBM6.label): This string is displayed if privacy.trackingprotection.ui.enabled is set to false. This currently happens on the release and beta channel. -->
-<!ENTITY trackingProtectionPBM5.label         "Use Tracking Protection in Private Windows">
-<!ENTITY trackingProtectionPBM5.accesskey     "v">
-<!-- LOCALIZATION NOTE (trackingProtectionPBM6.label): This string is displayed if privacy.trackingprotection.ui.enabled is set to false. This currently happens on the nightly channel. -->
 <!ENTITY trackingProtectionPBM6.label         "Use Tracking Protection in Private Browsing to block known trackers">
 <!ENTITY trackingProtectionPBM6.accesskey     "v">
 <!ENTITY trackingProtectionPBMLearnMore.label "Learn more">