Fix compilation with namespaces enabled

Reviewed-by: Samuel Rødal
(cherry picked from commit bff68fc7094a50af57f7da23ecf9b25cab00f188)

src/gui/painting/qcosmeticstroker.cpp

@@ -3,6 +3,8 @@
 #include <qdebug.h>
 #include <math.h>
 
+QT_BEGIN_NAMESPACE
+
 #if 0
 inline QString capString(int caps)
 {
@@ -952,3 +954,5 @@ static void drawLineAA(QCosmeticStroker *stroker, qreal rx1, qreal ry1, qreal rx
         }
     }
 }
+
+QT_END_NAMESPACE

src/gui/painting/qcosmeticstroker_p.h

@@ -6,6 +6,12 @@
 #include <private/qpaintengine_raster_p.h>
 #include <qpen.h>
 
+QT_BEGIN_HEADER
+
+QT_BEGIN_NAMESPACE
+
+QT_MODULE(Gui)
+
 class QCosmeticStroker;
 
 
@@ -98,4 +104,8 @@ public:
     bool clipLine(qreal &x1, qreal &y1, qreal &x2, qreal &y2);
 };
 
+QT_END_NAMESPACE
+
+QT_END_HEADER
+
 #endif // QCOSMETICLINE_H