Merge remote-tracking branch 'origin/5.9' into 5.10

 Conflicts:
	.qmake.conf
	mkspecs/win32-g++/qmake.conf
	src/corelib/global/qglobal_p.h
	src/corelib/global/qoperatingsystemversion_p.h
	src/corelib/io/qfilesystemengine_win.cpp
	src/network/bearer/qbearerengine.cpp
	src/platformsupport/input/libinput/qlibinputpointer.cpp
	src/sql/doc/snippets/code/doc_src_sql-driver.cpp
	src/widgets/kernel/qwidget_p.h
	src/widgets/kernel/qwidgetwindow.cpp
	src/widgets/styles/qfusionstyle.cpp
	tests/auto/corelib/io/qfileinfo/tst_qfileinfo.cpp

Change-Id: I80e2722f481b12fff5d967c28f89208c0e9a1dd8

1 files changed, 19 insertions, 6 deletions

diff --git a/src/widgets/widgets/qabstractscrollarea.cpp b/src/widgets/widgets/qabstractscrollarea.cpp
index 249ebd35d3..c6d66bafd4 100644
--- a/src/widgets/widgets/qabstractscrollarea.cpp
+++ b/src/widgets/widgets/qabstractscrollarea.cpp
@@ -334,16 +334,27 @@ void QAbstractScrollAreaPrivate::setSingleFingerPanEnabled(bool on)
 
 void QAbstractScrollAreaPrivate::layoutChildren()
 {
+    bool needH = false;
+    bool needV = false;
+    layoutChildren_helper(&needH, &needV);
+    // Call a second time if one scrollbar was needed and not the other to
+    // check if it needs to readjust accordingly
+    if (needH != needV)
+        layoutChildren_helper(&needH, &needV);
+}
+
+void QAbstractScrollAreaPrivate::layoutChildren_helper(bool *needHorizontalScrollbar, bool *needVerticalScrollbar)
+{
     Q_Q(QAbstractScrollArea);
     bool htransient = hbar->style()->styleHint(QStyle::SH_ScrollBar_Transient, 0, hbar);
-    bool needh = (hbarpolicy != Qt::ScrollBarAlwaysOff) && ((hbarpolicy == Qt::ScrollBarAlwaysOn && !htransient)
-                 || ((hbarpolicy == Qt::ScrollBarAsNeeded || htransient)
-                     && hbar->minimum() < hbar->maximum() && !hbar->sizeHint().isEmpty()));
+    bool needh = *needHorizontalScrollbar || ((hbarpolicy != Qt::ScrollBarAlwaysOff) && ((hbarpolicy == Qt::ScrollBarAlwaysOn && !htransient)
+                            || ((hbarpolicy == Qt::ScrollBarAsNeeded || htransient)
+                            && hbar->minimum() < hbar->maximum() && !hbar->sizeHint().isEmpty())));
 
     bool vtransient = vbar->style()->styleHint(QStyle::SH_ScrollBar_Transient, 0, vbar);
-    bool needv = (vbarpolicy != Qt::ScrollBarAlwaysOff) && ((vbarpolicy == Qt::ScrollBarAlwaysOn && !vtransient)
-                 || ((vbarpolicy == Qt::ScrollBarAsNeeded || vtransient)
-                     && vbar->minimum() < vbar->maximum() && !vbar->sizeHint().isEmpty()));
+    bool needv = *needVerticalScrollbar || ((vbarpolicy != Qt::ScrollBarAlwaysOff) && ((vbarpolicy == Qt::ScrollBarAlwaysOn && !vtransient)
+                            || ((vbarpolicy == Qt::ScrollBarAsNeeded || vtransient)
+                            && vbar->minimum() < vbar->maximum() && !vbar->sizeHint().isEmpty())));
 
     QStyleOption opt(0);
     opt.init(q);
@@ -522,6 +533,8 @@ void QAbstractScrollAreaPrivate::layoutChildren()
         viewportRect.adjust(left, top, -right, -bottom);
 
     viewport->setGeometry(QStyle::visualRect(opt.direction, opt.rect, viewportRect)); // resize the viewport last
+    *needHorizontalScrollbar = needh;
+    *needVerticalScrollbar = needv;
 }
 
 /*!