Add a NoStatePrefetch entry in about://flags

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 9b137b41d02dff19fd47f838364dd9d98dddfc58..23b97c542ff6b367d138fa94efd68d57e1a5e168 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -92696,6 +92696,7 @@ value.
   <int value="-204355195" label="secondary-ui-md"/>
   <int value="-195029497" label="MediaRemoting:disabled"/>
   <int value="-192919826" label="ViewsSimplifiedFullscreenUI:enabled"/>
+  <int value="-192389983" label="NoStatePrefetch:enabled"/>
   <int value="-183246373" label="enable-multilingual-spellchecker"/>
   <int value="-181093956" label="ScrollAnchoring:enabled"/>
   <int value="-165756594" label="enable-touch-feedback"/>
@@ -93005,6 +93006,7 @@ value.
   <int value="1302421166" label="NativeNotifications:disabled"/>
   <int value="1308537004" label="force-pnacl-subzero"/>
   <int value="1312025202" label="NTPOfflinePageSuggestions:disabled"/>
+  <int value="1314681756" label="NoStatePrefetch:disabled"/>
   <int value="1317562265" label="SeccompSandboxAndroid:disabled"/>
   <int value="1318073661" label="MaterialDesignExtensions:enabled"/>
   <int value="1319725131" label="enable-distance-field-text"/>