Include auto vertical scrollbar in intrinsicScrollbarLogicalWidth.

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

Index: third_party/WebKit/Source/core/layout/LayoutBox.cpp
diff --git a/third_party/WebKit/Source/core/layout/LayoutBox.cpp b/third_party/WebKit/Source/core/layout/LayoutBox.cpp
index c8a3f359e41ea58f55c8cc4f272d975c2f8e9123..6da2ae3925cc59cd4ce7dd0db605f46eacce14a7 100644
--- a/third_party/WebKit/Source/core/layout/LayoutBox.cpp
+++ b/third_party/WebKit/Source/core/layout/LayoutBox.cpp
@@ -793,12 +793,12 @@ int LayoutBox::intrinsicScrollbarLogicalWidth() const
 
     ASSERT(getScrollableArea());
 
-    if (isHorizontalWritingMode() && style()->overflowY() == OverflowScroll) {
+    if (isHorizontalWritingMode() && (style()->overflowY() == OverflowScroll || style()->overflowY() == OverflowAuto)) {

[skobes, 2016/05/16 20:55:53]

I will echo cbiesinger's question on the other thread :)

Can we kill this and just use scrollbarLogicalWidth?

         // Even with OverflowScroll, the scrollbar may not exist (crbug.com/415031).
         return getScrollableArea()->hasVerticalScrollbar() ? verticalScrollbarWidth() : 0;
     }
 
-    if (!isHorizontalWritingMode() && style()->overflowX() == OverflowScroll) {
+    if (!isHorizontalWritingMode() && (style()->overflowX() == OverflowScroll || style()->overflowX() == OverflowAuto)) {
         // Even with OverflowScroll, the scrollbar may not exist (crbug.com/415031).
         return getScrollableArea()->hasHorizontalScrollbar() ? horizontalScrollbarHeight() : 0;
     }