WebFonts intervention: understand if download time matches the decision

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 4ff3de352e501c39d7b1b4982b8fb5605c73bbd4..750b521133e0ac88354bf48b3ec5979ef2019665 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -109592,6 +109592,17 @@ value.
   <affected-histogram name="WebFont.DownloadTime.LoadError"/>
 </histogram_suffixes>
 
+<histogram_suffixes name="WebFontMissedCacheAndInterventionTriggeredOrNot"
+    separator="." ordering="prefix">
+  <owner>toyoshim@chromium.org</owner>
+  <suffix name="MissedCacheAndInterventionNotTriggered"
+      label="On missed cache and intervention not triggered"/>
+  <affected-histogram name="WebFont.DownloadTime.1.10KBTo50KB"/>
+  <suffix name="MissedCacheAndInterventionTriggered"
+      label="On missed cache and intervention triggered"/>
+  <affected-histogram name="WebFont.DownloadTime.1.10KBTo50KB"/>
+</histogram_suffixes>
+
 <histogram_suffixes name="WebRTCMediaType" separator=".">
   <suffix name="Audio" label="Audio"/>
   <suffix name="Video" label="Video"/>