exo: Drop window on touch release

components/exo/shell_surface.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 "components/exo/shell_surface.h"
 
 #include <algorithm>
 
 #include "ash/frame/custom_frame_view_ash.h"
 #include "ash/public/cpp/shelf_types.h"
@@ skipping 1107 matching lines @@
     case ui::ET_MOUSE_EXITED:
     case ui::ET_MOUSEWHEEL:
     case ui::ET_MOUSE_CAPTURE_CHANGED:
       break;
     default:
       NOTREACHED();
       break;
   }
 }
 
+void ShellSurface::OnGestureEvent(ui::GestureEvent* event) {
+  if (!resizer_) {
+    views::View::OnGestureEvent(event);
+    return;
+  }
+
+  if (event->handled())
+    return;
+
+  switch (event->type()) {
+    case ui::ET_GESTURE_END: {

[oshima, 2017/06/29 22:52:34]

if (type == ET_GESTURE_END) { ?

[Dominik Laskowski, 2017/06/30 17:45:44]

XDG clients can't be dragged/resized using touch, so we will need more cases
here.

+      ScopedConfigure scoped_configure(this, false);
+      EndDrag(false /* revert */);
+      break;
+    }
+
+    default: break;

[reveman, 2017/06/30 19:50:15]

nit: NOTREACHED() here and add other GESTURE events to switch statement so it's
clear that we're not failing to handle some event that we should be handling.

[Dominik Laskowski, 2017/06/30 20:50:06]

Checked the range instead to avoid 20+ cases.

+  }
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 // ui::AcceleratorTarget overrides:
 
 bool ShellSurface::AcceleratorPressed(const ui::Accelerator& accelerator) {
   for (const auto& entry : kCloseWindowAccelerators) {
     if (ui::Accelerator(entry.keycode, entry.modifiers) == accelerator) {
       if (!close_callback_.is_null())
         close_callback_.Run();
       return true;
     }
@@ skipping 549 matching lines @@
 gfx::Point ShellSurface::GetMouseLocation() const {
   aura::Window* const root_window = widget_->GetNativeWindow()->GetRootWindow();
   gfx::Point location =
       root_window->GetHost()->dispatcher()->GetLastMouseLocationInRoot();
   aura::Window::ConvertPointToTarget(
       root_window, widget_->GetNativeWindow()->parent(), &location);
   return location;
 }
 
 }  // namespace exo