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 c76ede7013547fb59a83bc9083d048173fe153f5..fbb90dbb4b005eed6970e135f4e850f9764f4701 100644
--- a/ash/shell_observer.h
+++ b/ash/shell_observer.h
@@ -48,6 +48,13 @@ 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() {}