Set caret width based on device scale factor

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

Index: third_party/WebKit/Source/core/layout/LayoutObject.cpp
diff --git a/third_party/WebKit/Source/core/layout/LayoutObject.cpp b/third_party/WebKit/Source/core/layout/LayoutObject.cpp
index e913d31e1340f849c08cc1f8b86a41dd5aee504c..d71183a3dbaf71a6ba527ed95dbf9c4fd00749a5 100644
--- a/third_party/WebKit/Source/core/layout/LayoutObject.cpp
+++ b/third_party/WebKit/Source/core/layout/LayoutObject.cpp
@@ -28,6 +28,8 @@
 
 #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"
@@ -77,6 +79,7 @@
 #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"
@@ -85,8 +88,6 @@
 #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
@@ -99,8 +100,8 @@ 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;
 }