Fix overflow in user traffic content type 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 b54a337982b557241462bc02932b41ab3b2aaa88..dcea9fe51b3b5d5716fccc85650371666a7804b2 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -10849,6 +10849,19 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 
 <histogram name="DataUse.ContentType.UserTraffic" enum="DataUseContentType"
     units="bytes">
+  <obsolete>
+    Deprecated 2017/04. Bytes are logged to DataUse.ContentType.UserTrafficKB.
+  </obsolete>
+  <owner>rajendrant@chromium.org</owner>
+  <owner>bengr@chromium.org</owner>
+  <summary>
+    Data use of user traffic by different content types. Recorded when network
+    bytes are received by Chrome.
+  </summary>
+</histogram>
+
+<histogram name="DataUse.ContentType.UserTrafficKB" enum="DataUseContentType"
+    units="KB">
   <owner>rajendrant@chromium.org</owner>
   <owner>bengr@chromium.org</owner>
   <summary>