linux-aura: Restore middle-click on new-tab button behaviour.

chrome/browser/ui/views/tabs/tab_strip.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 "chrome/browser/ui/views/tabs/tab_strip.h"
 
 #if defined(OS_WIN)
 #include <windowsx.h>
 #endif
 
@@ skipping 221 matching lines @@
       case ui::LAYOUT_TOUCH:
         value = 26;
         break;
       default:
         NOTREACHED();
     }
   }
   return value;
 }
 
+base::string16 GetClipboardText() {
+  if (!ui::Clipboard::IsSupportedClipboardType(ui::CLIPBOARD_TYPE_SELECTION))
+    return base::string16();
+  ui::Clipboard* clipboard = ui::Clipboard::GetForCurrentThread();
+  CHECK(clipboard);
+  base::string16 clipboard_text;
+  clipboard->ReadText(ui::CLIPBOARD_TYPE_SELECTION, &clipboard_text);
+  return clipboard_text;
+}
+
 // Animation delegate used when a dragged tab is released. When done sets the
 // dragging state to false.
 class ResetDraggingStateDelegate
     : public views::BoundsAnimator::OwnedAnimationDelegate {
  public:
   explicit ResetDraggingStateDelegate(Tab* tab) : tab_(tab) {
   }
 
   virtual void AnimationEnded(const gfx::Animation* animation) OVERRIDE {
     tab_->set_dragging(false);
@@ skipping 87 matching lines @@
   // were we destroyed?
   bool* destroyed_;
 
   DISALLOW_COPY_AND_ASSIGN(NewTabButton);
 };
 
 NewTabButton::NewTabButton(TabStrip* tab_strip, views::ButtonListener* listener)
     : views::ImageButton(listener),
       tab_strip_(tab_strip),
       destroyed_(NULL) {
+#if defined(OS_LINUX) && !defined(OS_CHROMEOS)
+  set_triggerable_event_flags(triggerable_event_flags() |
+                              ui::EF_MIDDLE_MOUSE_BUTTON);
+#endif
 }
 
 NewTabButton::~NewTabButton() {
   if (destroyed_)
     *destroyed_ = true;
 }
 
 bool NewTabButton::HasHitTestMask() const {
   // When the button is sized to the top of the tab strip we want the user to
   // be able to click on complete bounds, and so don't return a custom hit
@@ skipping 1145 matching lines @@
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 // TabStrip, views::ButtonListener implementation:
 
 void TabStrip::ButtonPressed(views::Button* sender, const ui::Event& event) {
   if (sender == newtab_button_) {
     content::RecordAction(UserMetricsAction("NewTab_Button"));
     UMA_HISTOGRAM_ENUMERATION("Tab.NewTab", TabStripModel::NEW_TAB_BUTTON,
                               TabStripModel::NEW_TAB_ENUM_COUNT);
+    if (event.IsMouseEvent()) {
+      const ui::MouseEvent& mouse = static_cast<const ui::MouseEvent&>(event);
+      if (mouse.IsOnlyMiddleMouseButton()) {
+        base::string16 clipboard_text = GetClipboardText();
+        controller()->CreateNewTabWithLocation(clipboard_text);

[Markus (顧孟勤), 2013/11/15 19:11:53]

Should we check whether clipboard_text is empty?

[sadrul, 2013/11/15 19:57:21]

Done.

+        return;
+      }
+    }
+
     controller()->CreateNewTab();
     if (event.type() == ui::ET_GESTURE_TAP)
       TouchUMA::RecordGestureAction(TouchUMA::GESTURE_NEWTAB_TAP);
   }
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 // TabStrip, protected:
 
 // Overridden to support automation. See automation_proxy_uitest.cc.
@@ skipping 1207 matching lines @@
 #if defined(USE_AURA)
   return chrome::GetHostDesktopTypeForNativeView(
       GetWidget()->GetNativeView()) == chrome::HOST_DESKTOP_TYPE_ASH;
 #else
   if (ui::GetDisplayLayout() != ui::LAYOUT_TOUCH)
     return false;
 #endif
 
   return true;
 }