Tab dragging as implemented as a mus API.

services/ui/public/cpp/lib/in_flight_change.h

Index: services/ui/public/cpp/lib/in_flight_change.h
diff --git a/services/ui/public/cpp/lib/in_flight_change.h b/services/ui/public/cpp/lib/in_flight_change.h
index 759a1bc6e84f366152f21b3086da1e658afb9e1f..93d96724b947204cf17da604aba361c03f4c148d 100644
--- a/services/ui/public/cpp/lib/in_flight_change.h
+++ b/services/ui/public/cpp/lib/in_flight_change.h
@@ -33,8 +33,9 @@ enum class ChangeType {
   CAPTURE,
   DELETE_WINDOW,
   FOCUS,
-  NEW_WINDOW,
+  MOVE_LOOP,
   NEW_TOP_LEVEL_WINDOW,
+  NEW_WINDOW,
   OPACITY,
   PREDEFINED_CURSOR,
   PROPERTY,
@@ -143,6 +144,18 @@ class InFlightBoundsChange : public InFlightChange {
   DISALLOW_COPY_AND_ASSIGN(InFlightBoundsChange);
 };
 
+class InFlightMoveLoopChange : public InFlightChange {
+ public:
+  explicit InFlightMoveLoopChange(Window* window);
+
+  // InFlightChange:
+  void SetRevertValueFrom(const InFlightChange& change) override;
+  void Revert() override;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(InFlightMoveLoopChange);
+};
+
 // Inflight change that crashes on failure. This is useful for changes that are
 // expected to always complete.
 class CrashInFlightChange : public InFlightChange {