Introduce moderate binding

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 59310e105767ca3eebf87f350b0b988231a54dbd..0e86fe05f2e885b4250ce92e939f90c8f2670f86 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -16971,6 +16971,14 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="MobileBindingManager.ModerateBindingCount">
+  <owner>jaekyun@chromium.org</owner>
+  <summary>
+    The number of moderate bindings which were kept while Chrome process is in
+    the foreground.
+  </summary>
+</histogram>
+
 <histogram name="MobileFre.SignInChoice" enum="MobileFreSignInChoice">
   <owner>aruslan@chromium.org</owner>
   <summary>
@@ -43912,6 +43920,14 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="Tab.TotalTabCountBeforeLeavingApp">
+  <owner>jaekyun@chromium.org</owner>
+  <summary>
+    The total count of tabs which were kept while Chrome process is in the
+    foreground.
+  </summary>
+</histogram>
+
 <histogram name="Tabs.CountAtResume" units="tabs">
   <owner>lliabraa@chromium.org</owner>
   <summary>