Fix problems with missing safety checks in Render::fillBuffer and pdfcomic

custom_widgets/yacreader_tool_bar_stretch.h

@@ -0,0 +1,18 @@
+#ifndef YACREADER_TOOL_BAR_STRETCH_H
+#define YACREADER_TOOL_BAR_STRETCH_H
+
+#include <QWidget>
+#include <QHBoxLayout>
+
+class YACReaderToolBarStretch : public QWidget
+{
+public:
+    YACReaderToolBarStretch(QWidget * parent=0):QWidget(parent)
+	{
+		QHBoxLayout * l= new QHBoxLayout();
+		l->addStretch();
+		setLayout(l);
+	}
+};
+
+#endif // YACREADER_TOOL_BAR_STRETCH_H