Set caret width based on device scale factor

third_party/WebKit/Source/core/layout/LayoutObject.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Dirk Mueller (mueller@kde.org)
  *           (C) 2004 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2011 Apple Inc.
  *               All rights reserved.
  * Copyright (C) 2009 Google Inc. All rights reserved.
  * Copyright (C) 2009 Torch Mobile Inc. All rights reserved.
  *               (http://www.torchmobile.com/)
@@ skipping 10 matching lines @@
  *
  * You should have received a copy of the GNU Library General Public License
  * along with this library; see the file COPYING.LIB.  If not, write to
  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  * Boston, MA 02110-1301, USA.
  *
  */
 
 #include "core/layout/LayoutObject.h"
 
+#include <algorithm>
+#include <memory>
 #include "core/animation/ElementAnimations.h"
 #include "core/css/resolver/StyleResolver.h"
 #include "core/dom/AXObjectCache.h"
 #include "core/dom/ElementTraversal.h"
 #include "core/dom/StyleChangeReason.h"
 #include "core/dom/StyleEngine.h"
 #include "core/dom/shadow/ShadowRoot.h"
 #include "core/editing/EditingUtilities.h"
 #include "core/editing/FrameSelection.h"
 #include "core/editing/TextAffinity.h"
@@ skipping 29 matching lines @@
 #include "core/layout/api/LayoutAPIShim.h"
 #include "core/layout/api/LayoutPartItem.h"
 #include "core/layout/ng/layout_ng_block_flow.h"
 #include "core/page/AutoscrollController.h"
 #include "core/page/Page.h"
 #include "core/paint/ObjectPaintInvalidator.h"
 #include "core/paint/ObjectPaintProperties.h"
 #include "core/paint/PaintLayer.h"
 #include "core/style/ContentData.h"
 #include "core/style/CursorData.h"
+#include "platform/HostWindow.h"
 #include "platform/InstanceCounters.h"
 #include "platform/RuntimeEnabledFeatures.h"
 #include "platform/geometry/TransformState.h"
 #include "platform/graphics/GraphicsLayer.h"
 #include "platform/instrumentation/tracing/TracedValue.h"
 #include "wtf/allocator/Partitions.h"
 #include "wtf/text/StringBuilder.h"
 #include "wtf/text/WTFString.h"
-#include <algorithm>
-#include <memory>
 #ifndef NDEBUG
 #include <stdio.h>
 #endif
 
 namespace blink {
 
 namespace {
 
 static bool gModifyLayoutTreeStructureAnyState = false;
 
 }  // namespace
 
-const LayoutUnit& caretWidth() {
-  static LayoutUnit gCaretWidth(1);
+const LayoutUnit& caretWidth(HostWindow* host) {
+  static LayoutUnit gCaretWidth(host->windowToViewportScalar(1));

[Xianzhu, 2017/02/10 22:53:55]

Does host->windowToViewportScalar(1) always return the same value in a process?

[oshima, 2017/02/10 22:57:23]

No, two tabs may have different scale factor.

[Xianzhu, 2017/02/10 23:04:13]

Then the above code is incorrect because the static variable is initialized only
once.

Please remove this function from LayoutObject.h/cpp and add

LayoutUnit FrameView::caretWidth() const {
  return getHostWindow()->windowToViewportScalar(1);
}

   return gCaretWidth;
 }
 
 #if DCHECK_IS_ON()
 
 LayoutObject::SetLayoutNeededForbiddenScope::SetLayoutNeededForbiddenScope(
     LayoutObject& layoutObject)
     : m_layoutObject(layoutObject),
       m_preexistingForbidden(m_layoutObject.isSetNeedsLayoutForbidden()) {
   m_layoutObject.setNeedsLayoutIsForbidden(true);
@@ skipping 3383 matching lines @@
     const blink::LayoutObject* root = object1;
     while (root->parent())
       root = root->parent();
     root->showLayoutTreeAndMark(object1, "*", object2, "-", 0);
   } else {
     WTFLogAlways("%s", "Cannot showLayoutTree. Root is (nil)");
   }
 }
 
 #endif