Add QEvent::StyleAnimationUpdate: style animation target should update

The event will be sent from the upcoming style animations. This change
merely introduces the new event type and makes both QWidget and
QGraphicsWidget call update() upon receiving the event.

Change-Id: I69bb4d05bacb22f7e3a2512cae68848801e4f4d7
Reviewed-by: Jens Bache-Wiig <jens.bache-wiig@digia.com>

src/corelib/kernel/qcoreevent.cpp

@@ -262,6 +262,7 @@ QT_BEGIN_NAMESPACE
     \omitvalue ShowWindowRequest
     \omitvalue Speech
     \omitvalue Style
+    \omitvalue StyleAnimationUpdate
     \omitvalue ZeroTimerEvent
     \omitvalue ApplicationActivated
     \omitvalue ApplicationDeactivated

src/corelib/kernel/qcoreevent.h

@@ -279,6 +279,8 @@ public:
 
         PlatformPanel = 212,
 
+        StyleAnimationUpdate = 213,             // style animation target should be updated
+
         // 512 reserved for Qt Jambi's MetaCall event
         // 513 reserved for Qt Jambi's DeleteOnMainThread event
 

src/widgets/graphicsview/qgraphicswidget.cpp

@@ -1408,6 +1408,7 @@ bool QGraphicsWidget::event(QEvent *event)
         break;
     case QEvent::WindowActivate:
     case QEvent::WindowDeactivate:
+    case QEvent::StyleAnimationUpdate:
         update();
         break;
         // Taken from QWidget::event

src/widgets/kernel/qwidget.cpp

@@ -8142,6 +8142,9 @@ bool QWidget::event(QEvent *event)
     case QEvent::UpdateLater:
         update(static_cast<QUpdateLaterEvent*>(event)->region());
         break;
+    case QEvent::StyleAnimationUpdate:
+        update();
+        break;
 
     case QEvent::WindowBlocked:
     case QEvent::WindowUnblocked: