CrOS Tablet Window management - Split Screen part I

ash/shell_observer.h

Index: ash/shell_observer.h
diff --git a/ash/shell_observer.h b/ash/shell_observer.h
index 44fa9d730abd60e1a0e9e8e55f573bb5b93c68a0..7f8a1463f0bd819310980650ae7887749530a932 100644
--- a/ash/shell_observer.h
+++ b/ash/shell_observer.h
@@ -52,6 +52,13 @@ class ASH_EXPORT ShellObserver {
   // Called after overview mode has ended.
   virtual void OnOverviewModeEnded() {}
 
+  // Called when the split view mode is about to be started (before the window
+  // gets snapped and activated).
+  virtual void OnSplitViewModeStarting() {}
+
+  // Called after split view mode has ended.
+  virtual void OnSplitViewModeEnded() {}
+
   // Called when the always maximize mode has started. Windows might still
   // animate though.
   virtual void OnMaximizeModeStarted() {}