testsuite: Add a test for previous fix

Fill a rectangle with fractional coordinates << 1.0 but scale it up so
that it ends up being nice integers.

Makes sure that nobody does any bad rounding here.

testsuite/gsk/compare/fill-scaled-up.node

@@ -0,0 +1,14 @@
+transform {
+  transform: scale(80);
+  child: container {
+    fill {
+      child: color {
+        bounds: -0.125 -0.125 0.25 0.25;
+        color: rgb(0,0,0);
+      }
+      path: "\
+M -0.125 -0.125 h 0.25 v 0.25 h -0.25 z";
+      fill-rule: winding;
+    }
+  }
+}

testsuite/gsk/meson.build

@@ -70,6 +70,7 @@ compare_render_tests = [
   'fill',
   'fill-clipped-nogl',
   'fill-opacity',
+  'fill-scaled-up',
   'fill-with-3d-contents-nogl-nocairo',
   'huge-height',
   'huge-width',