[Passwords] Extend PasswordManager.InaccessiblePasswords

While this metric is seeing low values now, this is one of the essential
health metrics for PwdMgr codebase that does help assess if there is a
wide spread encryption issue.

Fixed: 1153756
Change-Id: I260f8777250330cc550f40723e3511c0680462ef
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2595107
Auto-Submit: Mohamed Amir Yosef <mamir@chromium.org>
Commit-Queue: Ilya Sherman <isherman@chromium.org>
Reviewed-by: Ilya Sherman <isherman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#837804}

tools/metrics/histograms/histograms_xml/password/histograms.xml

@@ -1254,7 +1254,7 @@ reviews. Googlers can read more about this at go/gwsq-gerrit.
 </histogram>
 
 <histogram name="PasswordManager.InaccessiblePasswords" units="saved passwords"
-    expires_after="M89">
+    expires_after="M95">
   <owner>vasilii@chromium.org</owner>
   <owner>mamir@chromium.org</owner>
   <summary>