Cros Tablet: Add UMA stats for the user close actions in tablet mode.

tools/metrics/actions/actions.xml

Index: tools/metrics/actions/actions.xml
diff --git a/tools/metrics/actions/actions.xml b/tools/metrics/actions/actions.xml
index e88f1ff7956611f52a1b9d5a3ad2e517a95e27a6..b7ac934a8926eb84017f2efd60f999092c09902f 100644
--- a/tools/metrics/actions/actions.xml
+++ b/tools/metrics/actions/actions.xml
@@ -16589,6 +16589,30 @@ should be able to be added at any place in this file.
   <description>Please enter the description of this user action.</description>
 </action>
 
+<action name="Tablet_WindowCloseFromCaptionButton">
+  <owner>xdai@chromium.org</owner>
+  <description>
+    User closed the window through the close button in the caption area in
+    tablet mode on Chrome OS.
+  </description>
+</action>
+
+<action name="Tablet_WindowCloseFromContextMenu">
+  <owner>xdai@chromium.org</owner>
+  <description>
+    User closed the window through the shelf context menu in tablet mode on
+    Chrome OS.
+  </description>
+</action>
+
+<action name="Tablet_WindowCloseFromOverviewButton">
+  <owner>xdai@chromium.org</owner>
+  <description>
+    User closed the window through the close button in overview mode in tablet
+    mode on Chrome OS.
+  </description>
+</action>
+
 <action name="TaskManagement.OpenInChromeActionButtonClicked">
   <obsolete>The button option was removed and code deleted.</obsolete>
   <owner>dfalcantara@chromium.org</owner>