Fix scroll-bar behavior in RTL layout

Default to application layout direction when no widget is given,
and reverse meaning of position for horizontal RTL scrollbars.

Task-numer: QTBUG-28256
Change-Id: I09c49f5d104fd0b9a6b4b1cda5c754712fc26087
Reviewed-by: Michael Bruning <michael.bruning@digia.com>
Reviewed-by: Andras Becsi <andras.becsi@digia.com>

1 files changed, 7 insertions, 1 deletions

diff --git a/Source/WebCore/platform/qt/ScrollbarThemeQStyle.cpp b/Source/WebCore/platform/qt/ScrollbarThemeQStyle.cpp
index f89945771..d8c440b90 100644
--- a/Source/WebCore/platform/qt/ScrollbarThemeQStyle.cpp
+++ b/Source/WebCore/platform/qt/ScrollbarThemeQStyle.cpp
@@ -34,6 +34,8 @@
 #include "ScrollView.h"
 #include "Scrollbar.h"
 
+#include <QGuiApplication>
+
 namespace WebCore {
 
 ScrollbarThemeQStyle::ScrollbarThemeQStyle()
@@ -93,8 +95,10 @@ static QStyleFacadeOption initSliderStyleOption(ScrollbarThemeClient* scrollbar,
         opt.palette = widget->property("palette").value<QPalette>();
         opt.rect = widget->property("rect").value<QRect>();
         opt.direction = static_cast<Qt::LayoutDirection>(widget->property("layoutDirection").toInt());
-    } else
+    } else {
         opt.state |= QStyleFacade::State_Active;
+        opt.direction = QGuiApplication::layoutDirection();
+    }
 
     opt.state &= ~QStyleFacade::State_HasFocus;
 
@@ -116,6 +120,8 @@ static QStyleFacadeOption initSliderStyleOption(ScrollbarThemeClient* scrollbar,
     opt.slider.singleStep = scrollbar->lineStep();
     opt.slider.minimum = 0;
     opt.slider.maximum = qMax(0, scrollbar->maximum());
+    if (opt.slider.orientation == Qt::Horizontal && opt.direction == Qt::RightToLeft)
+        opt.slider.upsideDown = true;
     ScrollbarPart pressedPart = scrollbar->pressedPart();
     ScrollbarPart hoveredPart = scrollbar->hoveredPart();
     if (pressedPart != NoPart) {