Prevent TouchEvent Crash on X

ui/events/x/events_x_unittest.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 <cstring>
 #include <set>
 
 #include <X11/extensions/XInput2.h>
 #include <X11/Xlib.h>
 #include <X11/Xutil.h>
@@ skipping 335 matching lines @@
   // tracking id.
   ui::ScopedXI2Event xrelease1;
   xrelease1.InitTouchEvent(
       0, XI_TouchEnd, kTrackingId, gfx::Point(10, 10), valuators);
   {
     ui::TouchEvent urelease1(xrelease1);
   }
   EXPECT_EQ(-1, GetTouchIdForTrackingId(kTrackingId));
 }
 
+// Copied events should not remove native touch id mappings, as this causes a
+// crash (crbug.com/467102). Copied events do not contain a proper
+// base::NativeEvent and should not attempt to access it.
+TEST_F(EventsXTest, CopiedTouchEventNotRemovingFromNativeMapping) {
+  std::vector<unsigned int> devices;
+  devices.push_back(0);
+  ui::SetUpTouchDevicesForTest(devices);
+  std::vector<Valuator> valuators;
+
+  // Create a release event which has a native touch id mapping.
+  ui::ScopedXI2Event xrelease0;
+  xrelease0.InitTouchEvent(0, XI_TouchEnd, 0, gfx::Point(10, 10), valuators);
+  ui::TouchEvent urelease0(xrelease0);
+  {
+    // When the copy is destructed it should not attempt to remove the mapping.
+    // Exiting this scope should not cause a crash.
+    ui::TouchEvent copy = urelease0;
+  }
+}
+
 TEST_F(EventsXTest, NumpadKeyEvents) {
   XEvent event;
   Display* display = gfx::GetXDisplay();
 
   struct {
     bool is_numpad_key;
     int x_keysym;
   } keys[] = {
     // XK_KP_Space and XK_KP_Equal are the extrema in the conventional
     // keysymdef.h numbering.
@@ skipping 265 matching lines @@
         KeyEventTestApi test_event(&key_event);
         test_event.set_is_char(true);
       }
       EXPECT_FALSE(key_event.flags() & ui::EF_IME_FABRICATED_KEY);
     }
   }
 }
 #endif
 
 }  // namespace ui