diff -r 000000000000 -r 6474c204b198 layout/xul/nsTitleBarFrame.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/layout/xul/nsTitleBarFrame.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,172 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsCOMPtr.h"
+#include "nsTitleBarFrame.h"
+#include "nsIContent.h"
+#include "nsIDocument.h"
+#include "nsIDOMNodeList.h"
+#include "nsGkAtoms.h"
+#include "nsIWidget.h"
+#include "nsMenuPopupFrame.h"
+#include "nsPresContext.h"
+#include "nsIDocShell.h"
+#include "nsPIDOMWindow.h"
+#include "nsDisplayList.h"
+#include "nsContentUtils.h"
+#include "mozilla/MouseEvents.h"
+
+using namespace mozilla;
+
+//
+// NS_NewTitleBarFrame
+//
+// Creates a new TitleBar frame and returns it
+//
+nsIFrame*
+NS_NewTitleBarFrame(nsIPresShell* aPresShell, nsStyleContext* aContext)
+{
+  return new (aPresShell) nsTitleBarFrame(aPresShell, aContext);
+}
+
+NS_IMPL_FRAMEARENA_HELPERS(nsTitleBarFrame)
+
+nsTitleBarFrame::nsTitleBarFrame(nsIPresShell* aPresShell, nsStyleContext* aContext)
+:nsBoxFrame(aPresShell, aContext, false)
+{
+  mTrackingMouseMove = false;
+  UpdateMouseThrough();
+}
+
+void
+nsTitleBarFrame::BuildDisplayListForChildren(nsDisplayListBuilder*   aBuilder,
+                                             const nsRect&           aDirtyRect,
+                                             const nsDisplayListSet& aLists)
+{
+  // override, since we don't want children to get events
+  if (aBuilder->IsForEventDelivery()) {
+    if (!mContent->AttrValueIs(kNameSpaceID_None, nsGkAtoms::allowevents,
+                               nsGkAtoms::_true, eCaseMatters))
+      return;
+  }
+  nsBoxFrame::BuildDisplayListForChildren(aBuilder, aDirtyRect, aLists);
+}
+
+nsresult
+nsTitleBarFrame::HandleEvent(nsPresContext* aPresContext,
+                             WidgetGUIEvent* aEvent,
+                             nsEventStatus* aEventStatus)
+{
+  NS_ENSURE_ARG_POINTER(aEventStatus);
+  if (nsEventStatus_eConsumeNoDefault == *aEventStatus) {
+    return NS_OK;
+  }
+
+  bool doDefault = true;
+
+  switch (aEvent->message) {
+
+   case NS_MOUSE_BUTTON_DOWN:  {
+       if (aEvent->AsMouseEvent()->button == WidgetMouseEvent::eLeftButton) {
+         // titlebar has no effect in non-chrome shells
+         nsCOMPtr<nsIDocShellTreeItem> dsti = aPresContext->GetDocShell();
+         if (dsti) {
+           if (dsti->ItemType() == nsIDocShellTreeItem::typeChrome) {
+             // we're tracking.
+             mTrackingMouseMove = true;
+
+             // start capture.
+             nsIPresShell::SetCapturingContent(GetContent(), CAPTURE_IGNOREALLOWED);
+
+             // remember current mouse coordinates.
+             mLastPoint = LayoutDeviceIntPoint::ToUntyped(aEvent->refPoint);
+           }
+         }
+
+         *aEventStatus = nsEventStatus_eConsumeNoDefault;
+         doDefault = false;
+       }
+     }
+     break;
+
+
+   case NS_MOUSE_BUTTON_UP: {
+       if (mTrackingMouseMove &&
+           aEvent->AsMouseEvent()->button == WidgetMouseEvent::eLeftButton) {
+         // we're done tracking.
+         mTrackingMouseMove = false;
+
+         // end capture
+         nsIPresShell::SetCapturingContent(nullptr, 0);
+
+         *aEventStatus = nsEventStatus_eConsumeNoDefault;
+         doDefault = false;
+       }
+     }
+     break;
+
+   case NS_MOUSE_MOVE: {
+       if(mTrackingMouseMove)
+       {
+         nsIntPoint nsMoveBy = LayoutDeviceIntPoint::ToUntyped(aEvent->refPoint) - mLastPoint;
+
+         nsIFrame* parent = GetParent();
+         while (parent) {
+           nsMenuPopupFrame* popupFrame = do_QueryFrame(parent);
+           if (popupFrame)
+             break;
+           parent = parent->GetParent();
+         }
+
+         // if the titlebar is in a popup, move the popup frame, otherwise
+         // move the widget associated with the window
+         if (parent) {
+           nsMenuPopupFrame* menuPopupFrame = static_cast<nsMenuPopupFrame*>(parent);
+           nsCOMPtr<nsIWidget> widget = menuPopupFrame->GetWidget();
+           nsIntRect bounds;
+           widget->GetScreenBounds(bounds);
+
+           int32_t newx = aPresContext->DevPixelsToIntCSSPixels(bounds.x + nsMoveBy.x);
+           int32_t newy = aPresContext->DevPixelsToIntCSSPixels(bounds.y + nsMoveBy.y);
+           menuPopupFrame->MoveTo(newx, newy, false);
+         }
+         else {
+           nsIPresShell* presShell = aPresContext->PresShell();
+           nsPIDOMWindow *window = presShell->GetDocument()->GetWindow();
+           if (window) {
+             window->MoveBy(nsMoveBy.x, nsMoveBy.y);
+           }
+         }
+
+         *aEventStatus = nsEventStatus_eConsumeNoDefault;
+
+         doDefault = false;
+       }
+     }
+     break;
+
+    case NS_MOUSE_CLICK: {
+      WidgetMouseEvent* mouseEvent = aEvent->AsMouseEvent();
+      if (mouseEvent->IsLeftClickEvent()) {
+        MouseClicked(aPresContext, mouseEvent);
+      }
+      break;
+    }
+  }
+
+  if ( doDefault )
+    return nsBoxFrame::HandleEvent(aPresContext, aEvent, aEventStatus);
+  else
+    return NS_OK;
+}
+
+void
+nsTitleBarFrame::MouseClicked(nsPresContext* aPresContext,
+                              WidgetMouseEvent* aEvent)
+{
+  // Execute the oncommand event handler.
+  nsContentUtils::DispatchXULCommand(mContent,
+                                     aEvent && aEvent->mFlags.mIsTrusted);
+}