Clarify the size of a document view (a.k.a layout size) that causes FrameView to emit the resize ev…

Source/core/page/FrameView.cpp

 /*
  * Copyright (C) 1998, 1999 Torben Weis <weis@kde.org>
  *                     1999 Lars Knoll <knoll@kde.org>
  *                     1999 Antti Koivisto <koivisto@kde.org>
  *                     2000 Dirk Mueller <mueller@kde.org>
  * Copyright (C) 2004, 2005, 2006, 2007, 2008 Apple Inc. All rights reserved.
  *           (C) 2006 Graham Dennis (graham.dennis@gmail.com)
  *           (C) 2006 Alexey Proskuryakov (ap@nypop.com)
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
@@ skipping 113 matching lines @@
     RenderLayer::UpdateLayerPositionsFlags flags = RenderLayer::defaultFlags;
     if (didFullRepaint) {
         flags &= ~RenderLayer::CheckForRepaint;
         flags |= RenderLayer::NeedsFullRepaintInBacking;
     }
     if (isRelayoutingSubtree && layer->isPaginated())
         flags |= RenderLayer::UpdatePagination;
     return flags;
 }
 
+// The spec DOM Level 2 Events states that the resize event occurs when document view size (a.k.a layout size) is changed. Refer to http://www.w3.org/TR/DOM-Level-2-Events/events.html
+// However, showing/hiding scrollbars shouldn't be considered a layout size change. Refer to webkit.org/b/80242
+// viewportSize() is used to compare layout sizes between before and after to emit a resize event.
+static inline IntSize viewportSize(const FrameView* view)

[aelias_OOO_until_Jul13, 2013/05/29 18:47:28]

I suggest not having this static method and just calling view->layoutSize(). 
Please move the comment into your layout test.

+{
+    return view->layoutSize(ScrollView::IncludeScrollbars);
+}
+
 Pagination::Mode paginationModeForRenderStyle(RenderStyle* style)
 {
     EOverflow overflow = style->overflowY();
     if (overflow != OPAGEDX && overflow != OPAGEDY)
         return Pagination::Unpaginated;
 
     bool isHorizontalWritingMode = style->isHorizontalWritingMode();
     TextDirection textDirection = style->direction();
     WritingMode writingMode = style->writingMode();
 
@@ skipping 835 matching lines @@
             // Now set our scrollbar state for the layout.
             ScrollbarMode currentHMode = horizontalScrollbarMode();
             ScrollbarMode currentVMode = verticalScrollbarMode();
 
             if (m_firstLayout || (hMode != currentHMode || vMode != currentVMode)) {
                 if (m_firstLayout) {
                     setScrollbarsSuppressed(true);
 
                     m_firstLayout = false;
                     m_firstLayoutCallbackPending = true;
-                    m_lastViewportSize = visibleContentRect(IncludeScrollbars).size();
+                    m_lastViewportSize = viewportSize(this);
                     m_lastZoomFactor = root->style()->zoom();
 
                     // Set the initial vMode to AlwaysOn if we're auto.
                     if (vMode == ScrollbarAuto)
                         setVerticalScrollbarMode(ScrollbarAlwaysOn); // This causes a vertical scrollbar to appear.
                     // Set the initial hMode to AlwaysOff if we're auto.
                     if (hMode == ScrollbarAuto)
                         setHorizontalScrollbarMode(ScrollbarAlwaysOff); // This causes a horizontal scrollbar to disappear.
 
                     setScrollbarModes(hMode, vMode);
@@ skipping 1279 matching lines @@
 
     // Viewport-dependent media queries may cause us to need completely different style information.
     if (m_frame->document()->styleResolver()->affectedByViewportChange()) {
         m_frame->document()->styleResolverChanged(DeferRecalcStyle);
         InspectorInstrumentation::mediaQueryResultChanged(m_frame->document());
     }
 
     // Refetch render view since it can be destroyed by updateWidget() call above.
     renderView = this->renderView();
     if (renderView && !renderView->printing()) {
-        IntSize currentSize;
-        currentSize = visibleContentRect(IncludeScrollbars).size();
+        IntSize currentSize = viewportSize(this);
         float currentZoomFactor = renderView->style()->zoom();
         bool resized = !m_firstLayout && (currentSize != m_lastViewportSize || currentZoomFactor != m_lastZoomFactor);
         m_lastViewportSize = currentSize;
         m_lastZoomFactor = currentZoomFactor;
         if (resized) {
             m_frame->eventHandler()->sendResizeEvent();
             if (page && page->mainFrame() == m_frame)
                 InspectorInstrumentation::didResizeMainFrame(page);
         }
     }
@@ skipping 1102 matching lines @@
 }
 
 AXObjectCache* FrameView::axObjectCache() const
 {
     if (frame() && frame()->document())
         return frame()->document()->existingAXObjectCache();
     return 0;
 }
     
 } // namespace WebCore