Add UMA.IsClonedInstall boolean histogram.

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 e14b164bc0ef8eb6b6cb6a6d4da6f358070cb7bd..237176fd46bd170a670dd10116801f7ff4da5ab8 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -70770,6 +70770,15 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="UMA.IsClonedInstall" enum="BooleanCloned">
+  <owner>asvitkine@chromium.org</owner>
+  <summary>
+    This is logged with a value of true in every log when the UMA client code
+    has detected that this is a potentially cloned install and has set the pref
+    to reset its UMA client id on the next startup.
+  </summary>
+</histogram>
+
 <histogram name="UMA.Large Accumulated Log Not Persisted" units="bytes">
   <owner>asvitkine@chromium.org</owner>
   <summary>
@@ -79441,6 +79450,11 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   <int value="1" label="Clicked"/>
 </enum>
 
+<enum name="BooleanCloned" type="int">
+  <int value="0" label="Not cloned"/>
+  <int value="1" label="Cloned"/>
+</enum>
+
 <enum name="BooleanCloseTimeout" type="int">
   <int value="0" label="Closed normally"/>
   <int value="1" label="Timed out"/>