Revert 255385 "aura: Remove client::UserActionClient."

trunk/src/ui/views/widget/desktop_aura/desktop_window_tree_host_x11.cc

Index: trunk/src/ui/views/widget/desktop_aura/desktop_window_tree_host_x11.cc
===================================================================
--- trunk/src/ui/views/widget/desktop_aura/desktop_window_tree_host_x11.cc	(revision 255397)
+++ trunk/src/ui/views/widget/desktop_aura/desktop_window_tree_host_x11.cc	(working copy)
@@ -18,6 +18,7 @@
 #include "third_party/skia/include/core/SkPath.h"
 #include "ui/aura/client/cursor_client.h"
 #include "ui/aura/client/focus_client.h"
+#include "ui/aura/client/user_action_client.h"
 #include "ui/aura/window.h"
 #include "ui/aura/window_event_dispatcher.h"
 #include "ui/aura/window_property.h"
@@ -64,6 +65,10 @@
 
 namespace {
 
+// Standard Linux mouse buttons for going back and forward.
+const int kBackMouseButton = 8;
+const int kForwardMouseButton = 9;
+
 // Constants that are part of EWMH.
 const int k_NET_WM_STATE_ADD = 1;
 const int k_NET_WM_STATE_REMOVE = 0;
@@ -1296,7 +1301,20 @@
       SendEventToProcessor(&keyup_event);
       break;
     }
-    case ButtonPress:
+    case ButtonPress: {
+      if (static_cast<int>(xev->xbutton.button) == kBackMouseButton ||
+          static_cast<int>(xev->xbutton.button) == kForwardMouseButton) {
+        aura::client::UserActionClient* gesture_client =
+            aura::client::GetUserActionClient(dispatcher_->window());
+        if (gesture_client) {
+          gesture_client->OnUserAction(
+              static_cast<int>(xev->xbutton.button) == kBackMouseButton ?
+              aura::client::UserActionClient::BACK :
+              aura::client::UserActionClient::FORWARD);
+        }
+        break;
+      }
+    }  // fallthrough
     case ButtonRelease: {
       ui::EventType event_type = ui::EventTypeFromNative(xev);
       switch (event_type) {
@@ -1389,6 +1407,33 @@
             num_coalesced = ui::CoalescePendingMotionEvents(xev, &last_event);
             if (num_coalesced > 0)
               xev = &last_event;
+          } else if (type == ui::ET_MOUSE_PRESSED) {
+            XIDeviceEvent* xievent =
+                static_cast<XIDeviceEvent*>(xev->xcookie.data);
+            int button = xievent->detail;
+            if (button == kBackMouseButton || button == kForwardMouseButton) {
+              aura::client::UserActionClient* gesture_client =
+                  aura::client::GetUserActionClient(window());
+              if (gesture_client) {
+                bool reverse_direction =
+                    ui::IsTouchpadEvent(xev) && ui::IsNaturalScrollEnabled();
+                gesture_client->OnUserAction(
+                    (button == kBackMouseButton && !reverse_direction) ||
+                    (button == kForwardMouseButton && reverse_direction) ?
+                    aura::client::UserActionClient::BACK :
+                    aura::client::UserActionClient::FORWARD);
+              }
+              break;
+            }
+          } else if (type == ui::ET_MOUSE_RELEASED) {
+            XIDeviceEvent* xievent =
+                static_cast<XIDeviceEvent*>(xev->xcookie.data);
+            int button = xievent->detail;
+            if (button == kBackMouseButton || button == kForwardMouseButton) {
+              // We've already passed the back/forward mouse down to the user
+              // action client; we want to swallow the corresponding release.
+              break;
+            }
           }
           ui::MouseEvent mouseev(xev);
           DispatchMouseEvent(&mouseev);