bug 1374298 - revert in-place translation change. r=flod

MozReview-Commit-ID: 5kQYyUM3orn

--HG--
extra : rebase_source : d96048b42cb7f876ee21380b86834d7c2c3fb899

toolkit/locales/en-US/chrome/global/aboutTelemetry.dtd

@@ -29,11 +29,11 @@ Choose ping:
 ">
 
 <!ENTITY aboutTelemetry.showNewerPing "
-Newer ping &gt;&gt;
+&lt;&lt; Newer ping
 ">
 
 <!ENTITY aboutTelemetry.showOlderPing "
-&lt;&lt; Older ping
+Older ping &gt;&gt;
 ">
 
 <!ENTITY aboutTelemetry.archiveWeekHeader "