[librsvg] gradient.rs: Use Fragment instead of String for the fallback name

[Federico Mena Quintero <federico src gnome org>]

commit f0e7f42d43dc99ca3ef0485263844c26d1e8913c
Author: Federico Mena Quintero <federico gnome org>
Date:   Thu Nov 29 17:59:41 2018 -0600

    gradient.rs: Use Fragment instead of String for the fallback name

 rsvg_internals/src/gradient.rs | 15 +++++++++------
 rsvg_internals/src/util.rs     | 11 -----------
 2 files changed, 9 insertions(+), 17 deletions(-)
---
diff --git a/rsvg_internals/src/gradient.rs b/rsvg_internals/src/gradient.rs
index a4533039..eb6846e3 100644
--- a/rsvg_internals/src/gradient.rs
+++ b/rsvg_internals/src/gradient.rs
@@ -6,6 +6,7 @@ use std::cell::RefCell;
 use attributes::Attribute;
 use bbox::*;
 use coord_units::CoordUnits;
+use defs::Fragment;
 use drawing_ctx::{AcquiredNode, DrawingCtx};
 use error::*;
 use handle::RsvgHandle;
@@ -18,7 +19,6 @@ use rect::RectangleExt;
 use state::{ComputedValues, StopColor};
 use stop::*;
 use unitinterval::UnitInterval;
-use util::clone_fallback_name;
 
 #[derive(Copy, Clone)]
 pub struct ColorStop {
@@ -85,7 +85,7 @@ pub struct GradientCommon {
     pub units: Option<GradientUnits>,
     pub affine: Option<cairo::Matrix>,
     pub spread: Option<SpreadMethod>,
-    pub fallback: Option<String>,
+    pub fallback: Option<Fragment>,
     pub stops: Option<Vec<ColorStop>>,
 }
 
@@ -184,7 +184,7 @@ impl GradientCommon {
         fallback_to!(self.spread, fallback.spread);
         fallback_to!(self.stops, fallback.clone_stops());
 
-        self.fallback = clone_fallback_name(&fallback.fallback);
+        self.fallback = fallback.fallback.clone();
     }
 
     fn add_color_stop(&mut self, mut offset: f64, rgba: cssparser::RGBA, opacity: UnitInterval) {
@@ -430,8 +430,8 @@ impl Gradient {
     }
 }
 
-fn acquire_gradient<'a>(draw_ctx: &'a mut DrawingCtx<'_>, name: &str) -> Option<AcquiredNode> {
-    if let Some(acquired) = draw_ctx.get_acquired_href(name) {
+fn acquire_gradient<'a>(draw_ctx: &'a mut DrawingCtx<'_>, name: &Fragment) -> Option<AcquiredNode> {
+    if let Some(acquired) = draw_ctx.get_acquired_node(name) {
         let node_type = acquired.get().get_type();
 
         if node_type == NodeType::LinearGradient || node_type == NodeType::RadialGradient {
@@ -671,7 +671,10 @@ impl NodeTrait for NodeGradient {
                     g.common.spread = Some(parse("spreadMethod", value, ())?)
                 }
 
-                Attribute::XlinkHref => g.common.fallback = Some(value.to_owned()),
+                Attribute::XlinkHref => {
+                    g.common.fallback =
+                        Some(Fragment::parse(value).attribute(Attribute::XlinkHref)?)
+                }
 
                 // Attributes specific to each gradient type.  The defaults mandated by the spec
                 // are in GradientVariant::resolve_from_defaults()
diff --git a/rsvg_internals/src/util.rs b/rsvg_internals/src/util.rs
index ab5cd5be..3a7c7cac 100644
--- a/rsvg_internals/src/util.rs
+++ b/rsvg_internals/src/util.rs
@@ -5,17 +5,6 @@ use std::str;
 
 use glib::translate::*;
 
-// In paint servers (patterns, gradients, etc.), we have an
-// Option<String> for fallback names.  This is a utility function to
-// clone one of those.
-pub fn clone_fallback_name(fallback: &Option<String>) -> Option<String> {
-    if let Some(ref fallback_name) = *fallback {
-        Some(fallback_name.clone())
-    } else {
-        None
-    }
-}
-
 /// Converts a `char *` which is known to be valid UTF-8 into a `&str`
 ///
 /// The usual `from_glib_none(s)` allocates an owned String.  The