Delay expiry of histograms causing alerts.

Updates the expires_after attribute for 3 histograms that have
been used to generate alerts in the past 90 days and do not already have
a date later than or within 60 days of 2021-02-22.

TBR=chromium-metrics-reviews@google.com

Change-Id: I3bdbe8dd9c2ea644aab3c998fb2019059aeb80ee
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2557785Reviewed-by: Chrome Metrics Logs <chrome-metrics-team+robot@google.com>
Reviewed-by: Weilun Shi <sweilun@chromium.org>
Commit-Queue: Chrome Metrics Logs <chrome-metrics-team+robot@google.com>
Commit-Queue: Weilun Shi <sweilun@chromium.org>
Cr-Commit-Position: refs/heads/master@{#830639}

tools/metrics/histograms/histograms_xml/omnibox/histograms.xml

@@ -64,7 +64,7 @@ reviews. Googlers can read more about this at go/gwsq-gerrit.
 </histogram>
 
 <histogram name="Omnibox.CharTypedToRepaintLatency" units="ms"
-    expires_after="2021-03-23">
+    expires_after="2021-05-23">
   <owner>jdonnelly@chromium.org</owner>
   <owner>mpearson@chromium.org</owner>
   <owner>asvitkine@chromium.org</owner>

tools/metrics/histograms/histograms_xml/others/histograms.xml

@@ -7642,7 +7642,7 @@ reviews. Googlers can read more about this at go/gwsq-gerrit.
 </histogram>
 
 <histogram name="Kiosk.Launch.CryptohomeFailure" enum="LoginFailureReason"
-    expires_after="2021-03-21">
+    expires_after="2021-05-23">
   <owner>xiyuan@chromium.org</owner>
   <owner>apotapchuk@chromium.org</owner>
   <summary>Tracks cryptohome failure during kiosk launch.</summary>
@@ -17118,7 +17118,7 @@ regressions. -->
 </histogram>
 
 <histogram name="WebFont.CacheHit" enum="WebFontCacheHit"
-    expires_after="2021-03-21">
+    expires_after="2021-05-23">
   <owner>hajimehoshi@chromium.org</owner>
   <owner>kenjibaheux@chromium.org</owner>
   <owner>kouhei@chromium.org</owner>