Drag and drop cleans up touch sequences from the source window.

chrome/browser/ui/views/tabs/tab_drag_controller.cc

 // Copyright (c) 2012 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 "chrome/browser/ui/views/tabs/tab_drag_controller.h"
 
 #include <math.h>
 #include <set>
 
 #include "base/auto_reset.h"
@@ skipping 562 matching lines @@
 
   if (!target_tabstrip) {
     DetachIntoNewBrowserAndRunMoveLoop(point_in_screen);
     return DRAG_BROWSER_RESULT_STOP;
   }
 
 #if defined(USE_AURA)
   // Only Aura windows are gesture consumers.
   ui::GestureRecognizer::Get()->TransferEventsTo(
       GetAttachedBrowserWidget()->GetNativeView(),
-      target_tabstrip->GetWidget()->GetNativeView());
+      target_tabstrip->GetWidget()->GetNativeView(),
+      ui::GestureRecognizer::ShouldCancelTouches::DontCancel);
 #endif
 
   if (is_dragging_window_) {
     // ReleaseCapture() is going to result in calling back to us (because it
     // results in a move). That'll cause all sorts of problems.  Reset the
     // observer so we don't get notified and process the event.
 #if defined(USE_ASH)
     move_loop_widget_->RemoveObserver(this);
     move_loop_widget_ = nullptr;
 #endif  // USE_ASH
@@ skipping 434 matching lines @@
 
   BrowserView* dragged_browser_view =
       BrowserView::GetBrowserViewForBrowser(browser);
   views::Widget* dragged_widget = dragged_browser_view->GetWidget();
 
 #if defined(USE_AURA)
   // Only Aura windows are gesture consumers.
   gfx::NativeView attached_native_view =
       attached_tabstrip_->GetWidget()->GetNativeView();
   ui::GestureRecognizer::Get()->TransferEventsTo(
-      attached_native_view, dragged_widget->GetNativeView());
+      attached_native_view, dragged_widget->GetNativeView(),
+      ui::GestureRecognizer::ShouldCancelTouches::DontCancel);
 #endif
 
   Detach(can_release_capture_ ? RELEASE_CAPTURE : DONT_RELEASE_CAPTURE);
 
   dragged_widget->SetVisibilityChangedAnimationsEnabled(false);
   Attach(dragged_browser_view->tabstrip(), gfx::Point());
   AdjustBrowserAndTabBoundsForDrag(last_tabstrip_width,
                                    point_in_screen,
                                    &drag_bounds);
   WindowPositionManagedUpdater updater;
@@ skipping 755 matching lines @@
   // TODO(pkotwicz): Fix this properly (crbug.com/358482)
   for (auto* browser : *BrowserList::GetInstance()) {
     if (browser->tab_strip_model()->empty())
       exclude.insert(browser->window()->GetNativeWindow());
   }
 #endif
   base::WeakPtr<TabDragController> ref(weak_factory_.GetWeakPtr());
   *window = window_finder_->GetLocalProcessWindowAtPoint(screen_point, exclude);
   return ref ? Liveness::ALIVE : Liveness::DELETED;
 }