Allows tab dragging when maximized on aura. To fix it I made it so

ash/wm/property_util.h

Index: ash/wm/property_util.h
diff --git a/ash/wm/property_util.h b/ash/wm/property_util.h
index aa19dda4141ee149944ce567a11571ebb399e8a1..01ab2bc50836330f722f1da54ced3841dfd24ac8 100644
--- a/ash/wm/property_util.h
+++ b/ash/wm/property_util.h
@@ -10,6 +10,8 @@
 
 namespace aura {
 class Window;
+template<typename T>
+struct WindowProperty;
 }
 
 namespace gfx {
@@ -37,6 +39,16 @@ ASH_EXPORT void ClearRestoreBounds(aura::Window* window);
 // Toggles the maximized state of the specified window.
 ASH_EXPORT void ToggleMaximizedState(aura::Window* window);
 
+ASH_EXPORT extern const aura::WindowProperty<bool>* const
+    kWindowTrackedByWorkspaceSplitPropKey;
+
+// Sets whether the specified window is tracked by workspace code. Default is
+// true. If set to false the workspace does not switch the current workspace,
+// nor does it attempt to impose constraints on the bounds of the window. This
+// is intended for tab dragging.
+ASH_EXPORT void SetTrackedByWorkspace(aura::Window* window, bool value);
+ASH_EXPORT bool GetTrackedByWorkspace(aura::Window* window);
+
 }
 
 #endif  // ASH_WM_PROPERTY_UTIL_H_