Bug 1031267 - Fix --enable-system-cairo builds after they were broken by bug 1027763. r=jwatt

gfx/2d/DrawTargetCairo.cpp

@@ -413,7 +413,9 @@ DrawTargetCairo::GetType() const
     case CAIRO_SURFACE_TYPE_RECORDING:
     case CAIRO_SURFACE_TYPE_DRM:
     case CAIRO_SURFACE_TYPE_SUBSURFACE:
+#ifdef CAIRO_HAS_D2D_SURFACE
     case CAIRO_SURFACE_TYPE_D2D:
+#endif
     case CAIRO_SURFACE_TYPE_TEE: // included to silence warning about unhandled enum value
       return DrawTargetType::SOFTWARE_RASTER;
     }