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

YACReaderLibrary/qml/InfoTick.qml

@@ -0,0 +1,29 @@
+import QtQuick 2.6
+
+import QtGraphicalEffects 1.0
+
+Item {
+
+    property bool read
+
+    signal readChangedByUser(bool read)
+
+    MouseArea {
+        anchors.fill: read_compact
+        onClicked: {
+            readChangedByUser(!read);
+        }
+    }
+
+    Image {
+        id: read_compact
+        source: "info-tick.png"
+    }
+
+    ColorOverlay {
+        anchors.fill: read_compact
+        source: read_compact
+        color: read ? readTickCheckedColor : readTickUncheckedColor
+    }
+}
+