Remove unused histograms

tools/metrics/histograms/histograms.xml

Index: tools/metrics/histograms/histograms.xml
diff --git a/tools/metrics/histograms/histograms.xml b/tools/metrics/histograms/histograms.xml
index 44d8e14aa2542c704920e814f96086b274716577..3e1c64a94b3f8703a484bf9e12468997a211d736 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -33526,6 +33526,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="Net.CRLRequestFailedTimeMs" units="ms">
+  <obsolete>
+    Deprecated 2017-04-21 as it was Linux/CrOS only.
+  </obsolete>
   <owner>rsleevi@chromium.org</owner>
   <summary>
     When validating an HTTPS certificate we may have to block to fetch one or
@@ -33535,6 +33538,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="Net.CRLRequestSuccess" enum="BooleanSuccess">
+  <obsolete>
+    Deprecated 2017-04-21 as it was Linux/CrOS only.
+  </obsolete>
   <owner>rsleevi@chromium.org</owner>
   <summary>
     When validating an HTTPS certificate we may have to block to fetch one or
@@ -33543,6 +33549,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="Net.CRLRequestTimeMs" units="ms">
+  <obsolete>
+    Deprecated 2017-04-21 as it was Linux/CrOS only.
+  </obsolete>
   <owner>rsleevi@chromium.org</owner>
   <summary>
     When validating an HTTPS certificate we may have to block to fetch one or
@@ -35451,6 +35460,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="Net.OCSPRequestFailedTimeMs" units="ms">
+  <obsolete>
+    Deprecated 2017-04-21 as it was Linux/CrOS only.
+  </obsolete>
   <owner>rsleevi@chromium.org</owner>
   <summary>
     When validating an HTTPS certificate we may have to make one or more HTTP
@@ -35460,6 +35472,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="Net.OCSPRequestSuccess" enum="BooleanSuccess">
+  <obsolete>
+    Deprecated 2017-04-21 as it was Linux/CrOS only.
+  </obsolete>
   <owner>rsleevi@chromium.org</owner>
   <summary>
     When validating an HTTPS certificate we may have to make one or more HTTP
@@ -35469,6 +35484,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="Net.OCSPRequestTimeMs" units="ms">
+  <obsolete>
+    Deprecated 2017-04-21 as it was Linux/CrOS only.
+  </obsolete>
   <owner>rsleevi@chromium.org</owner>
   <summary>
     When validating an HTTPS certificate we may have to make one or more HTTP