WebFonts: measure network loading time

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 ccb015218961048b5dfb1b1cfa73160813bd231d..e02796b7f98ea30d59f63e4af2018d47a42a10f2 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -105196,6 +105196,17 @@ To add a new entry, add it with any value and run test to compute valid value.
   <affected-histogram name="WebFont.DecodeSpeed"/>
 </histogram_suffixes>
 
+<histogram_suffixes name="WebFontMissedCache" separator="." ordering="prefix">
+  <owner>toyoshim@chromium.org</owner>
+  <suffix name="MissedCache" label="On missed cache"/>
+  <affected-histogram name="WebFont.DownloadTime.0.Under10KB"/>
+  <affected-histogram name="WebFont.DownloadTime.1.10KBTo50KB"/>
+  <affected-histogram name="WebFont.DownloadTime.2.50KBTo100KB"/>
+  <affected-histogram name="WebFont.DownloadTime.3.100KBTo1MB"/>
+  <affected-histogram name="WebFont.DownloadTime.4.Over1MB"/>
+  <affected-histogram name="WebFont.DownloadTime.LoadError"/>
+</histogram_suffixes>
+
 <histogram_suffixes name="WebRTCMediaType" separator=".">
   <suffix name="Audio" label="Audio"/>
   <suffix name="Video" label="Video"/>