Add support for new scroll valuators coming from CMT

ui/aura/root_window_host_linux.cc

 // Copyright (c) 2011 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.h"
 
 #include <X11/cursorfont.h>
 #include <X11/Xlib.h>
 
 // Get rid of a macro from Xlib.h that conflicts with Aura's RootWindow class.
 #undef RootWindow
 
 #include <algorithm>
 
 #include "base/message_loop.h"
 #include "base/message_pump_x.h"
 #include "ui/aura/cursor.h"
 #include "ui/aura/event.h"
 #include "ui/aura/root_window.h"
 #include "ui/base/keycodes/keyboard_codes.h"
 #include "ui/base/touch/touch_factory.h"
+#include "ui/base/x/scroll_factory.h"
 #include "ui/base/x/x11_util.h"
 #include "ui/gfx/compositor/layer.h"
 
 #include <X11/cursorfont.h>
 #include <X11/extensions/XInput2.h>
 #include <X11/Xlib.h>
 
 using std::max;
 using std::min;
 
@@ skipping 158 matching lines @@
     // with one from the master and one from the slave so there will
     // always be at least one pending.
     if (!ui::TouchFactory::GetInstance()->ShouldProcessXI2Event(&next_event)) {
       CheckXEventForConsistency(&next_event);
       XFreeEventData(display, &next_event.xcookie);
       XNextEvent(display, &next_event);
       continue;
     }
 
     if (next_event.type == GenericEvent &&
-        next_event.xgeneric.evtype == XI_Motion) {
+        next_event.xgeneric.evtype == XI_Motion &&
+        !ui::ScrollFactory::GetInstance()->GetScrollOffsets(
+            next_event, NULL, NULL)) {
       XIDeviceEvent* next_xievent =
           static_cast<XIDeviceEvent*>(next_event.xcookie.data);
       // Confirm that the motion event is targeted at the same window
       // and that no buttons or modifiers have changed.
       if (xievent->event == next_xievent->event &&
           xievent->child == next_xievent->child &&
           xievent->buttons.mask_len == next_xievent->buttons.mask_len &&
           (memcmp(xievent->buttons.mask,
                   next_xievent->buttons.mask,
                   xievent->buttons.mask_len) == 0) &&
@@ skipping 204 matching lines @@
       if (size_changed)
         root_window_->OnHostResized(bounds.size());
       handled = true;
       break;
     }
     case GenericEvent: {
       ui::TouchFactory* factory = ui::TouchFactory::GetInstance();
       if (!factory->ShouldProcessXI2Event(xev))
         break;
 
+      // Update the device list if necessary.
+      if (xev->xgeneric.evtype == XI_HierarchyChanged) {
+        ui::ScrollFactory::GetInstance()->UpdateDeviceList(xdisplay_);
+        factory->UpdateDeviceList(xdisplay_);
+        handled = true;
+        break;
+      }
+
+      ui::EventType type = ui::EventTypeFromNative(xev);
       // If this is a motion event we want to coalesce all pending motion
       // events that are at the top of the queue.
       XEvent last_event;
       int num_coalesced = 0;
-      if (xev->xgeneric.evtype == XI_Motion) {
-        num_coalesced = CoalescePendingXIMotionEvents(xev, &last_event);
-        if (num_coalesced > 0)
-          xev = &last_event;
-      }
 
-      ui::EventType type = ui::EventTypeFromNative(xev);
       switch (type) {
         case ui::ET_TOUCH_PRESSED:
         case ui::ET_TOUCH_RELEASED:
         case ui::ET_TOUCH_MOVED: {
           TouchEvent touchev(xev);
           handled = root_window_->DispatchTouchEvent(&touchev);
           break;
         }
+        case ui::ET_MOUSE_MOVED:
+        case ui::ET_MOUSE_DRAGGED: {
+          // If this is a motion event we want to coalesce all pending motion
+          // events that are at the top of the queue.
+          num_coalesced = CoalescePendingXIMotionEvents(xev, &last_event);
+          if (num_coalesced > 0)
+            xev = &last_event;
+        }
         case ui::ET_MOUSE_PRESSED:
         case ui::ET_MOUSE_RELEASED:
-        case ui::ET_MOUSE_MOVED:
-        case ui::ET_MOUSE_DRAGGED:
         case ui::ET_MOUSEWHEEL:
         case ui::ET_MOUSE_ENTERED:
         case ui::ET_MOUSE_EXITED: {
           MouseEvent mouseev(xev);
           handled = root_window_->DispatchMouseEvent(&mouseev);
           break;
         }
+        case ui::ET_SCROLL: {
+          ScrollEvent scrollev(xev);
+          handled = root_window_->DispatchScrollEvent(&scrollev);
+          break;
+        }
         case ui::ET_UNKNOWN:
           handled = false;
           break;
         default:
           NOTREACHED();
       }
 
       // If we coalesced an event we need to free its cookie.
       if (num_coalesced > 0)
         XFreeEventData(xev->xgeneric.display, &last_event.xcookie);
@@ skipping 165 matching lines @@
   return new RootWindowHostLinux(bounds);
 }
 
 // static
 gfx::Size RootWindowHost::GetNativeScreenSize() {
   ::Display* xdisplay = base::MessagePumpX::GetDefaultXDisplay();
   return gfx::Size(DisplayWidth(xdisplay, 0), DisplayHeight(xdisplay, 0));
 }
 
 }  // namespace aura