Add slave touch device to touch_device_lookup_ and touch_device_list_

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 <stddef.h>
 #include <X11/Xatom.h>
 #include <X11/cursorfont.h>
 #include <X11/extensions/XInput.h>
@@ skipping 107 matching lines @@
 
     if (devinfo.use == XIFloatingSlave || devinfo.use == XISlavePointer) {
       for (int k = 0; k < devinfo.num_classes; ++k) {
         XIAnyClassInfo* xiclassinfo = devinfo.classes[k];
         if (xiclassinfo->type == XITouchClass) {
           XITouchClassInfo* tci =
               reinterpret_cast<XITouchClassInfo*>(xiclassinfo);
           // Only care direct touch device (such as touch screen) right now
           if (tci->mode == XIDirectTouch) {
             CacheTouchscreenIds(devinfo.deviceid);
+            touch_device_lookup_[devinfo.deviceid] = true;
+            touch_device_list_[devinfo.deviceid] = false;

[sadrul, 2016/12/12 16:02:06]

I think this is getting fairly confusing. Can you merge the two loops (this one,
and the one in line ~102:111)? Because they are beginning to look really
similar.

             if (devinfo.use == XISlavePointer) {
               device_master_id_list_[devinfo.deviceid] = devinfo.attachment;
               // If the slave device is direct touch device, we also set its
               // master device to be touch device.
               touch_device_lookup_[devinfo.attachment] = true;

[sadrul, 2016/12/12 16:02:06]

Oh hrm. We should really verify that |devinfo.attachment| does not go out of
bounds.

               touch_device_list_[devinfo.attachment] = true;
             }
           }
         }
       }
     }
   }
 }
 
 bool TouchFactory::ShouldProcessXI2Event(XEvent* xev) {
   DCHECK_EQ(GenericEvent, xev->type);
   XIEvent* event = static_cast<XIEvent*>(xev->xcookie.data);
   XIDeviceEvent* xiev = reinterpret_cast<XIDeviceEvent*>(event);
 
   const bool is_touch_disabled = !touch_screens_enabled_;
 
   if (event->evtype == XI_TouchBegin ||
       event->evtype == XI_TouchUpdate ||
       event->evtype == XI_TouchEnd) {
+    // TODO(chaopeng) we need to add deviceid to touch_device_lookup_ if this
+    // assertion failed.
+    DCHECK(touch_device_lookup_[xiev->deviceid]);
     // Since SetupXI2ForXWindow() selects events from all devices, for a
     // touchscreen attached to a master pointer device, X11 sends two
     // events for each touch: one from the slave (deviceid == the id of
     // the touchscreen device), and one from the master (deviceid == the
     // id of the master pointer device). Instead of processing both
     // events, discard the event that comes from the slave, and only
     // allow processing the event coming from the master.
     // For a 'floating' touchscreen device, X11 sends only one event for
     // each touch, with both deviceid and sourceid set to the id of the
     // touchscreen device.
@@ skipping 165 matching lines @@
       std::find_if(touchscreens.begin(), touchscreens.end(),
                    [device_id](const TouchscreenDevice& touchscreen) {
                      return touchscreen.id == device_id;
                    });
   // Internal displays will have a vid and pid of 0. Ignore them.
   if (it != touchscreens.end() && it->vendor_id && it->product_id)
     touchscreen_ids_.insert(std::make_pair(it->vendor_id, it->product_id));
 }
 
 }  // namespace ui