Fix grabbing capture when the mouse is pressed on Desktop Linux.

ui/events/devices/x11/touch_factory_x11.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 "ui/events/devices/x11/touch_factory_x11.h"
 
 #include <X11/Xatom.h>
 #include <X11/cursorfont.h>
 #include <X11/extensions/XInput.h>
 #include <X11/extensions/XInput2.h>
@@ skipping 187 matching lines @@
   memset(mask, 0, sizeof(mask));
 
   XISetMask(mask, XI_TouchBegin);
   XISetMask(mask, XI_TouchUpdate);
   XISetMask(mask, XI_TouchEnd);
 
   XISetMask(mask, XI_ButtonPress);
   XISetMask(mask, XI_ButtonRelease);
   XISetMask(mask, XI_Motion);
 #if defined(OS_CHROMEOS)
+  // XGrabKey() must be replaced with XI2 keyboard grab if XI2 key events are
+  // enabled on desktop Linux.
   if (base::SysInfo::IsRunningOnChromeOS()) {
     XISetMask(mask, XI_KeyPress);
     XISetMask(mask, XI_KeyRelease);
   }
 #endif
 
   XIEventMask evmask;
   evmask.deviceid = XIAllDevices;
   evmask.mask_len = sizeof(mask);
   evmask.mask = mask;
@@ skipping 120 matching lines @@
       if (ptr[0] || ptr[1])
         touchscreen_ids_.insert(std::make_pair(ptr[0], ptr[1]));
     }
     XFree(prop_return);
   }
 
   XCloseDevice(display, device);
 }
 
 }  // namespace ui