gsk: Keep metrics hinting on when rendering

It turns out that we mispositioned glyphs with some cff fonts
when metrics hinting is off, and hinting is on. Since we don't
fully understand the interactions of these settings at this point,
lets preserve metrics hinting as it was on the font we got.

This at least gives folks a workaround for when they experience
clipped rendering with cff fonts: Turn on hint-metrics.

We forced hint metrics off here because it made Pango do some
creative wfh for hex boxes at small sizes, but I've dropped that
on the Pango side.

gsk/gpu/gskgpudevice.c

@@ -918,12 +918,7 @@ gsk_gpu_device_lookup_glyph_image (GskGpuDevice           *self,
       return cache->image;
     }
 
-  /* Note: we want to scale the font to the required size *and* ensure that
-   * metrics hinting is off. The latter is necessary since pango lets metrics
-   * hinting influence the rendering of hexboxes, and we get bad outcomes if
-   * that happens.
-   */
-  scaled_font = gsk_reload_font (font, scale, CAIRO_HINT_METRICS_OFF, CAIRO_HINT_STYLE_DEFAULT, CAIRO_ANTIALIAS_DEFAULT);
+  scaled_font = gsk_reload_font (font, scale, CAIRO_HINT_METRICS_DEFAULT, CAIRO_HINT_STYLE_DEFAULT, CAIRO_ANTIALIAS_DEFAULT);
 
   subpixel_x = (flags & 3) / 4.f;
   subpixel_y = ((flags >> 2) & 3) / 4.f;