mus: Implement interwindow drag and drop

services/ui/public/cpp/in_flight_change.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "services/ui/public/cpp/in_flight_change.h"
 
 #include "services/ui/public/cpp/window_private.h"
 #include "services/ui/public/cpp/window_tree_client.h"
 
 namespace ui {
@@ skipping 21 matching lines @@
 
 void InFlightBoundsChange::SetRevertValueFrom(const InFlightChange& change) {
   revert_bounds_ =
       static_cast<const InFlightBoundsChange&>(change).revert_bounds_;
 }
 
 void InFlightBoundsChange::Revert() {
   WindowPrivate(window()).LocalSetBounds(window()->bounds(), revert_bounds_);
 }
 
-// InFlightMoveLoopChange -----------------------------------------------------
+// InFlightDragChange -----------------------------------------------------
 
-InFlightMoveLoopChange::InFlightMoveLoopChange(Window* window)
-    : InFlightChange(window, ChangeType::MOVE_LOOP) {}
+InFlightDragChange::InFlightDragChange(Window* window, ChangeType type)
+    : InFlightChange(window, type) {
+  DCHECK(type == ChangeType::MOVE_LOOP || type == ChangeType::DRAG_LOOP);
+}
 
-void InFlightMoveLoopChange::SetRevertValueFrom(const InFlightChange& change) {}
+void InFlightDragChange::SetRevertValueFrom(const InFlightChange& change) {}
 
-void InFlightMoveLoopChange::Revert() {
-  // Reverting bounds happens in the window server in the error case; it cannot
-  // happen in the client because this could conflict with a
-  // InFlightBoundsChange.
-}
+void InFlightDragChange::Revert() {}
 
 // CrashInFlightChange --------------------------------------------------------
 
 CrashInFlightChange::CrashInFlightChange(Window* window, ChangeType type)
     : InFlightChange(window, type) {}
 
 CrashInFlightChange::~CrashInFlightChange() {}
 
 void CrashInFlightChange::SetRevertValueFrom(const InFlightChange& change) {
   CHECK(false);
@@ skipping 160 matching lines @@
 
 InFlightSetModalChange::~InFlightSetModalChange() {}
 
 void InFlightSetModalChange::SetRevertValueFrom(const InFlightChange& change) {}
 
 void InFlightSetModalChange::Revert() {
   WindowPrivate(window()).LocalUnsetModal();
 }
 
 }  // namespace ui