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 282e08cc67fdf3f1425686fa10f571cd7224a88a..66f4c910a82cdabee083bb801f33223c281bd592 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() {}