aura-x11: Install the dispatcher as a message-pump observer.

ui/aura/root_window_host_linux.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/aura/root_window_host_linux.h"
 
 #include <X11/Xatom.h>
 #include <X11/Xcursor/Xcursor.h>
 #include <X11/cursorfont.h>
 #include <X11/extensions/XInput2.h>
@@ skipping 29 matching lines @@
 
 // Standard Linux mouse buttons for going back and forward.
 const int kBackMouseButton = 8;
 const int kForwardMouseButton = 9;
 
 const char kRootWindowHostLinuxKey[] = "__AURA_ROOT_WINDOW_HOST_LINUX__";
 
 // The events reported for slave devices can have incorrect information for some
 // fields. This utility function is used to check for such inconsistencies.
 void CheckXEventForConsistency(XEvent* xevent) {
-#if defined(USE_XI2_MT)
+#if defined(USE_XI2_MT) && !defined(NDEBUG)

[sadrul, 2012/05/16 17:07:01]

I was tempted to just remove this check since we have switched to XI2.2 and the
code it is supposed to check is not used anymore. But I am keeping it only for
debug builds since it has caught event-dispatching bugs in a couple of places,
and may find other such cases.

   static bool expect_master_event = false;
   static XIDeviceEvent slave_event;
   static gfx::Point slave_location;
   static int slave_button;
 
   // Note: If an event comes from a slave pointer device, then it will be
   // followed by the same event, but reported from its master pointer device.
   // However, if the event comes from a floating slave device (e.g. a
   // touchscreen), then it will not be followed by a duplicate event, since the
   // floating slave isn't attached to a master.
@@ skipping 24 matching lines @@
     CHECK_EQ(slave_event.evtype, xievent->evtype);
     CHECK_EQ(slave_button, ui::EventButtonFromNative(xevent));
     CHECK_EQ(slave_event.flags, xievent->flags);
     CHECK_EQ(slave_event.buttons.mask_len, xievent->buttons.mask_len);
     CHECK_EQ(slave_event.valuators.mask_len, xievent->valuators.mask_len);
     CHECK_EQ(slave_event.mods.base, xievent->mods.base);
     CHECK_EQ(slave_event.mods.latched, xievent->mods.latched);
     CHECK_EQ(slave_event.mods.locked, xievent->mods.locked);
     CHECK_EQ(slave_event.mods.effective, xievent->mods.effective);
   }
-#endif  // defined(USE_XI2_MT)
+#endif  // defined(USE_XI2_MT) && !defined(NDEBUG)
 }
 
 // Returns X font cursor shape from an Aura cursor.
 int CursorShapeFromNative(gfx::NativeCursor native_cursor) {
   switch (native_cursor.native_type()) {
     case ui::kCursorNull:
       return XC_left_ptr;
     case ui::kCursorPointer:
       return XC_left_ptr;
     case ui::kCursorCross:
@@ skipping 761 matching lines @@
       ui::ViewProp::GetValue(accelerated_widget, kRootWindowHostLinuxKey));
 }
 
 // static
 gfx::Size RootWindowHost::GetNativeScreenSize() {
   ::Display* xdisplay = base::MessagePumpX::GetDefaultXDisplay();
   return gfx::Size(DisplayWidth(xdisplay, 0), DisplayHeight(xdisplay, 0));
 }
 
 }  // namespace aura