[librsvg: 10/12] marker.rs: Add back comment that got removed during clippy

[Federico Mena Quintero <federico src gnome org>]

commit f041560fa7426cb664f91d893e6d2cd7a6b886ec
Author: Federico Mena Quintero <federico gnome org>
Date:   Mon Jan 8 08:47:51 2018 -0600

    marker.rs: Add back comment that got removed during clippy

 rust/src/marker.rs | 2 ++
 1 file changed, 2 insertions(+)
---
diff --git a/rust/src/marker.rs b/rust/src/marker.rs
index 3672f4f..3d1b509 100644
--- a/rust/src/marker.rs
+++ b/rust/src/marker.rs
@@ -382,6 +382,8 @@ pub fn path_builder_to_segments (builder: &RsvgPathBuilder) -> Vec<Segment> {
     }
 
     if let SegmentState::NewSubpath = state {
+        // Output a lone point if we started a subpath with a moveto
+        // command, but there are no subsequent commands.
         segments.push (make_degenerate (cur_x, cur_y));
     };