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

ash/wm/property_util.cc

Index: ash/wm/property_util.cc
diff --git a/ash/wm/property_util.cc b/ash/wm/property_util.cc
index e3b577d2aa11667b4c39dd74dd92984199736116..2e5440c4ca8a500941730fb248995390e5529897 100644
--- a/ash/wm/property_util.cc
+++ b/ash/wm/property_util.cc
@@ -7,11 +7,20 @@
 #include "ash/wm/window_util.h"
 #include "ui/aura/client/aura_constants.h"
 #include "ui/aura/window.h"
+#include "ui/aura/window_property.h"
 #include "ui/base/ui_base_types.h"
 #include "ui/gfx/rect.h"
 
+DECLARE_WINDOW_PROPERTY_TYPE(bool)
+
 namespace ash {
 
+namespace {
+
+const aura::WindowProperty<bool> kWindowTrackedByWorkspaceSplitProp = {true};
+
+}  // namespace
+
 void SetRestoreBounds(aura::Window* window, const gfx::Rect& bounds) {
   scoped_ptr<const gfx::Rect> old_bounds(GetRestoreBounds(window));
   window->SetProperty(aura::client::kRestoreBoundsKey, new gfx::Rect(bounds));
@@ -37,4 +46,15 @@ void ToggleMaximizedState(aura::Window* window) {
                                                     : ui::SHOW_STATE_MAXIMIZED);
 }
 
+const aura::WindowProperty<bool>* const
+    kWindowTrackedByWorkspaceSplitPropKey = &kWindowTrackedByWorkspaceSplitProp;
+
+void SetTrackedByWorkspace(aura::Window* window, bool value) {
+  window->SetProperty(kWindowTrackedByWorkspaceSplitPropKey, value);
+}
+
+bool GetTrackedByWorkspace(aura::Window* window) {
+  return window->GetProperty(kWindowTrackedByWorkspaceSplitPropKey);
+}
+
 }