Autosizing storage doesnot belong on FrameView

Source/core/frame/FrameViewAutoSizeInfo.cpp

+// 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 "config.h"
+#include "core/frame/FrameViewAutoSizeInfo.h"
+
+#include "core/frame/FrameView.h"
+#include "core/frame/LocalFrame.h"
+#include "core/rendering/RenderBox.h"
+#include "core/rendering/RenderView.h"
+
+namespace blink {
+
+FrameViewAutoSizeInfo::FrameViewAutoSizeInfo(FrameView* view)
+    : m_frameView(view)
+    , m_inAutoSize(false)
+    , m_didRunAutosize(false)
+{
+    ASSERT(m_frameView);
+}
+
+FrameViewAutoSizeInfo::~FrameViewAutoSizeInfo()
+{
+    removeAutoSizeMode();
+}
+
+void FrameViewAutoSizeInfo::configureAutoSizeMode(const IntSize& minSize, const IntSize& maxSize)
+{
+    ASSERT(!minSize.isEmpty());
+    ASSERT(minSize.width() <= maxSize.width());
+    ASSERT(minSize.height() <= maxSize.height());
+
+    if (m_minAutoSize == minSize && m_maxAutoSize == maxSize)
+        return;
+
+    m_minAutoSize = minSize;
+    m_maxAutoSize = maxSize;
+    m_didRunAutosize = false;
+
+    m_frameView->setLayoutSizeFixedToFrameSize(true);
+    m_frameView->setNeedsLayout();
+    m_frameView->scheduleRelayout();
+}
+
+void FrameViewAutoSizeInfo::removeAutoSizeMode()
+{
+    m_frameView->setLayoutSizeFixedToFrameSize(false);
+    m_frameView->setNeedsLayout();
+    m_frameView->scheduleRelayout();
+
+    // Since autosize mode forces the scrollbar mode, change them to being auto.
+    m_frameView->setVerticalScrollbarLock(false);
+    m_frameView->setHorizontalScrollbarLock(false);
+    m_frameView->setScrollbarModes(ScrollbarAuto, ScrollbarAuto);
+}
+
+void FrameViewAutoSizeInfo::autoSizeIfNeeded()
+{
+    if (m_inAutoSize)
+        return;
+
+    TemporaryChange<bool> changeInAutoSize(m_inAutoSize, true);
+
+    Document* document = m_frameView->frame().document();
+    if (!document || !document->isActive())
+        return;
+
+    Element* documentElement = document->documentElement();
+    if (!documentElement)
+        return;
+
+    // If this is the first time we run autosize, start from small height and
+    // allow it to grow.
+    if (!m_didRunAutosize)
+        m_frameView->resize(m_frameView->frameRect().width(), m_minAutoSize.height());
+
+    IntSize size = m_frameView->frameRect().size();
+
+    // Do the resizing twice. The first time is basically a rough calculation using the preferred width
+    // which may result in a height change during the second iteration.
+    for (int i = 0; i < 2; i++) {
+        // Update various sizes including contentsSize, scrollHeight, etc.
+        document->updateLayoutIgnorePendingStylesheets();
+
+        RenderView* renderView = document->renderView();
+        if (!renderView)
+            return;
+
+        int width = renderView->minPreferredLogicalWidth();
+
+        RenderBox* documentRenderBox = documentElement->renderBox();
+        if (!documentRenderBox)
+            return;
+
+        int height = documentRenderBox->scrollHeight();
+        IntSize newSize(width, height);
+
+        // Check to see if a scrollbar is needed for a given dimension and
+        // if so, increase the other dimension to account for the scrollbar.
+        // Since the dimensions are only for the view rectangle, once a
+        // dimension exceeds the maximum, there is no need to increase it further.
+        if (newSize.width() > m_maxAutoSize.width()) {
+            RefPtr<Scrollbar> localHorizontalScrollbar = m_frameView->horizontalScrollbar();
+            if (!localHorizontalScrollbar)
+                localHorizontalScrollbar = m_frameView->createScrollbar(HorizontalScrollbar);
+            if (!localHorizontalScrollbar->isOverlayScrollbar())
+                newSize.setHeight(newSize.height() + localHorizontalScrollbar->height());
+
+            // Don't bother checking for a vertical scrollbar because the width is at
+            // already greater the maximum.
+        } else if (newSize.height() > m_maxAutoSize.height()) {
+            RefPtr<Scrollbar> localVerticalScrollbar = m_frameView->verticalScrollbar();
+            if (!localVerticalScrollbar)
+                localVerticalScrollbar = m_frameView->createScrollbar(VerticalScrollbar);
+            if (!localVerticalScrollbar->isOverlayScrollbar())
+                newSize.setWidth(newSize.width() + localVerticalScrollbar->width());
+
+            // Don't bother checking for a horizontal scrollbar because the height is
+            // already greater the maximum.
+        }
+
+        // Ensure the size is at least the min bounds.
+        newSize = newSize.expandedTo(m_minAutoSize);
+
+        // Bound the dimensions by the max bounds and determine what scrollbars to show.
+        ScrollbarMode horizonalScrollbarMode = ScrollbarAlwaysOff;
+        if (newSize.width() > m_maxAutoSize.width()) {
+            newSize.setWidth(m_maxAutoSize.width());
+            horizonalScrollbarMode = ScrollbarAlwaysOn;
+        }
+        ScrollbarMode verticalScrollbarMode = ScrollbarAlwaysOff;
+        if (newSize.height() > m_maxAutoSize.height()) {
+            newSize.setHeight(m_maxAutoSize.height());
+            verticalScrollbarMode = ScrollbarAlwaysOn;
+        }
+
+        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_frameView->frame().document()->loadEventFinished() && (newSize.height() < size.height() || newSize.width() < size.width()))
+            break;
+
+        m_frameView->resize(newSize.width(), newSize.height());
+        // 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).
+        m_frameView->setVerticalScrollbarLock(false);
+        m_frameView->setHorizontalScrollbarLock(false);
+        m_frameView->setScrollbarModes(horizonalScrollbarMode, verticalScrollbarMode, true, true);
+    }
+    m_didRunAutosize = true;
+}
+
+} // namespace blink