Refactor fixed layout mode

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 185 matching lines @@
 {
     RefPtr<FrameView> view = adoptRef(new FrameView(frame));
     view->show();
     return view.release();
 }
 
 PassRefPtr<FrameView> FrameView::create(Frame* frame, const IntSize& initialSize)
 {
     RefPtr<FrameView> view = adoptRef(new FrameView(frame));
     view->Widget::setFrameRect(IntRect(view->location(), initialSize));
+    view->setLayoutSize(initialSize);
+
     view->show();
     return view.release();
 }
 
 FrameView::~FrameView()
 {
     if (m_postLayoutTasksTimer.isActive()) {
         m_postLayoutTasksTimer.stop();
         m_overflowEventQueue.clear();
     }
@@ skipping 833 matching lines @@
                         setHorizontalScrollbarMode(ScrollbarAlwaysOff); // This causes a horizontal scrollbar to disappear.
 
                     setScrollbarModes(hMode, vMode);
                     setScrollbarsSuppressed(false, true);
                 } else
                     setScrollbarModes(hMode, vMode);
             }
 
             LayoutSize oldSize = m_size;
 
-            m_size = LayoutSize(layoutWidth(), layoutHeight());
+            m_size = LayoutSize(layoutSize().width(), layoutSize().height());
 
             if (oldSize != m_size) {
                 m_doFullRepaint = true;
                 if (!m_firstLayout) {
                     RenderBox* rootRenderer = document->documentElement() ? document->documentElement()->renderBox() : 0;
                     RenderBox* bodyRenderer = rootRenderer && document->body() ? document->body()->renderBox() : 0;
                     if (bodyRenderer && bodyRenderer->stretchesToViewport())
                         bodyRenderer->setChildNeedsLayout();
                     else if (rootRenderer && rootRenderer->stretchesToViewport())
                         rootRenderer->setChildNeedsLayout();
@@ skipping 35 matching lines @@
 
     if (AXObjectCache* cache = rootForThisLayout->document().existingAXObjectCache())
         cache->postNotification(rootForThisLayout, AXObjectCache::AXLayoutComplete, true);
     updateAnnotatedRegions();
 
     ASSERT(partialLayout().isStopping() || !rootForThisLayout->needsLayout());
 
     updateCanBlitOnScrollRecursively();
 
     if (document->hasListenerType(Document::OVERFLOWCHANGED_LISTENER))
-        updateOverflowStatus(layoutWidth() < contentsWidth(), layoutHeight() < contentsHeight());
+        updateOverflowStatus(layoutSize().width() < contentsWidth(), layoutSize().height() < contentsHeight());
 
     scheduleOrPerformPostLayoutTasks();
 
     InspectorInstrumentation::didLayout(cookie, rootForThisLayout);
 
     m_nestedLayoutCount--;
     if (m_nestedLayoutCount)
         return;
 
     if (partialLayout().isStopping())
@@ skipping 473 matching lines @@
     if (!hasViewportConstrainedObjects())
         return;
 
     ViewportConstrainedObjectSet::const_iterator end = m_viewportConstrainedObjects->end();
     for (ViewportConstrainedObjectSet::const_iterator it = m_viewportConstrainedObjects->begin(); it != end; ++it) {
         RenderObject* renderer = *it;
         renderer->setNeedsLayout();
     }
 }
 
+IntSize FrameView::layoutSize(IncludeScrollbarsInRect scrollbarInclusion) const
+{
+    return scrollbarInclusion == ExcludeScrollbars ? excludeScrollbars(m_layoutSize) : m_layoutSize;
+}
+
+void FrameView::setLayoutSize(const IntSize& size)
+{
+    if (m_layoutSize == size)
+        return;
+
+    m_layoutSize = size;
+    contentsResized();
+}
 
 void FrameView::scrollPositionChanged()
 {
     m_frame->eventHandler()->sendScrollEvent();
     m_frame->eventHandler()->dispatchFakeMouseMoveEventSoon();
 
     if (RenderView* renderView = this->renderView()) {
         if (renderView->usesCompositing())
             renderView->compositor()->frameViewDidScroll();
     }
@@ skipping 96 matching lines @@
 
     ScrollView::repaintContentRectangle(r);
 }
 
 void FrameView::contentsResized()
 {
     ScrollView::contentsResized();
     setNeedsLayout();
 }
 
-void FrameView::visibleContentsResized()
+void FrameView::scrollbarExistenceDidChange()
 {
     // We check to make sure the view is attached to a frame() as this method can
     // be triggered before the view is attached by Frame::createView(...) setting
     // various values such as setScrollBarModes(...) for example.  An ASSERT is
     // triggered when a view is layout before being attached to a frame().
     if (!frame().view())
         return;
 
-    if (!useFixedLayout() && needsLayout())
+    if (!m_frame->page()->settings().viewportEnabled() && needsLayout())

[aelias_OOO_until_Jul13, 2013/10/01 05:09:30]

Checking viewportEnabled here doesn't seem very principled.  How about checking
if they're overlay scrollbars instead?

[bokan, 2013/10/02 17:44:01]

A few unit tests in WebFrameTest fail when I check for that instead. I'm
assuming they're checking Clank/WebView specific behaviour but the tests don't
have the lverlay scrollbars theme enabled. Does WebView use overlay scrollbars
as well? If it does I can fix the tests and change this. 

[aelias_OOO_until_Jul13, 2013/10/02 18:59:59]

Yes, both Clank and WebView always use overlay scrollbars.  You can go ahead and
update all the WebFrameTests that enable the viewport tag to also activate the
overlay scrollbar theme.

[bokan, 2013/10/02 21:27:26]

Done.

         layout();
 
     if (RenderView* renderView = this->renderView()) {
         if (renderView->usesCompositing())
             renderView->compositor()->frameViewDidChangeSize();
     }
 }
 
 void FrameView::beginDeferredRepaints()
 {
@@ skipping 657 matching lines @@
         if (newSize == size)
             continue;
 
         // While loading only allow the size to increase (to avoid twitching during intermediate smaller states)
         // unless autoresize has just been turned on or the maximum size is smaller than the current size.
         if (m_didRunAutosize && size.height() <= m_maxAutoSize.height() && size.width() <= m_maxAutoSize.width()
             && !m_frame->document()->loadEventFinished() && (newSize.height() < size.height() || newSize.width() < size.width()))
             break;
 
         resize(newSize.width(), newSize.height());
+        setLayoutSize(newSize);
         // Force the scrollbar state to avoid the scrollbar code adding them and causing them to be needed. For example,
         // a vertical scrollbar may cause text to wrap and thus increase the height (which is the only reason the scollbar is needed).
         setVerticalScrollbarLock(false);
         setHorizontalScrollbarLock(false);
         setScrollbarModes(horizonalScrollbarMode, verticalScrollbarMode, true, true);
     }
     m_didRunAutosize = true;
 }
 
 void FrameView::updateOverflowStatus(bool horizontalOverflow, bool verticalOverflow)
@@ skipping 986 matching lines @@
     if (frame().document())
         return frame().document()->existingAXObjectCache();
     return 0;
 }
 
 bool FrameView::isMainFrame() const
 {
     return m_frame->page() && m_frame->page()->mainFrame() == m_frame;
 }
 
+void FrameView::frameRectsChanged()
+{
+    Document* doc = m_frame->document();
+    bool layoutSizeIsExplicitlySet = m_frame->page() && m_frame->page()->mainFrame() == m_frame

[aelias_OOO_until_Jul13, 2013/10/01 05:09:30]

Instead of this, how about a public method
FrameView::setLayoutSizeMatchesFrameSize(bool), make the boolean default to true
and only set it false from WebViewImpl?

[bokan, 2013/10/02 17:44:01]

Done, only I set it false from Frame::createView

+        && doc && (doc->isHTMLDocument() || doc->isXHTMLDocument());
+
+    // Non-main frames' layout size should always match the frame size. For main frames we
+    // explicitly set the layout size from WebViewImpl
+    if (!layoutSizeIsExplicitlySet)
+        setLayoutSize(frameRect().size());
+
+    ScrollView::frameRectsChanged();
+}
+
 } // namespace WebCore