GestureLongPress should be able to invoke BUBBLE_MODE_FAST_USER_SWITCH.

chrome/browser/ui/views/profiles/new_avatar_button.cc

 // Copyright 2014 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 "chrome/browser/ui/views/profiles/new_avatar_button.h"
 
 #include "base/win/windows_version.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/profiles/profile_manager.h"
 #include "chrome/browser/profiles/profiles_state.h"
@@ skipping 114 matching lines @@
   return LabelButton::OnMousePressed(event);
 }
 
 void NewAvatarButton::OnMouseReleased(const ui::MouseEvent& event) {
   if (suppress_mouse_released_action_)
     suppress_mouse_released_action_ = false;
   else
     LabelButton::OnMouseReleased(event);
 }
 
+void NewAvatarButton::OnGestureEvent(ui::GestureEvent* event) {
+  // TODO(wjmaclean): The check for ET_GESTURE_LONG_PRESS is done here since
+  // no other UI button based on CustomButton appears to handle mouse
+  // right-click. If other cases are identified, it may make sense to move this
+  // check to CustomButton.
+  if (event->type() == ui::ET_GESTURE_LONG_PRESS)
+    NotifyClick(*event);
+  else
+    LabelButton::OnGestureEvent(event);
+}
+
 void NewAvatarButton::OnProfileAdded(const base::FilePath& profile_path) {
   Update();
 }
 
 void NewAvatarButton::OnProfileWasRemoved(
       const base::FilePath& profile_path,
       const base::string16& profile_name) {
   // If deleting the active profile, don't bother updating the avatar
   // button, as the browser window is being closed anyway.
   if (browser_->profile()->GetPath() != profile_path)
@@ skipping 57 matching lines @@
     SetImage(views::Button::STATE_NORMAL, gfx::ImageSkia());
   }
 
   // If we are not using the generic button, then reset the spacing between
   // the text and the possible authentication error icon.
   const int kDefaultImageTextSpacing = 5;
   SetImageLabelSpacing(use_generic_button ? 0 : kDefaultImageTextSpacing);
 
   PreferredSizeChanged();
 }