Record shutdown type UMA

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 edfe252772965e0350e02f6d75f453a54ef84ed6..3c1bebf129444b9a2a0c4bee52ac7e496826e1dc 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -55689,6 +55689,11 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="Shutdown.ShutdownType" enum="ShutdownType">
+  <owner>hashimoto@chromium.org</owner>
+  <summary>The type of the last shutdown.</summary>
+</histogram>
+
 <histogram name="Signin" enum="SigninHelperFlow">
   <owner>mlerman@chromium.org</owner>
   <summary>
@@ -94699,6 +94704,13 @@ To add a new entry, add it with any value and run test to compute valid value.
   <int value="6" label="Dark resume failed"/>
 </enum>
 
+<enum name="ShutdownType" type="int">
+  <int value="0" label="Not valid">Invalid value.</int>
+  <int value="1" label="Window close">The last browser window was closed.</int>
+  <int value="2" label="Browser exit">User clicked on the Exit menu item.</int>
+  <int value="3" label="End session">OS is logging off or shutting down.</int>
+</enum>
+
 <enum name="SideloadUIEvents" type="int">
   <int value="0" label="Extension installed"/>
   <int value="1" label="Extension ignored"/>