gnu: arc-icon-theme: Move to gnome-xyz.

* gnu/packages/gnome.scm (arc-icon-theme): Move from here...
* gnu/packages/gnome-xyz.scm (arc-icon-theme): ... to here.

gnu/packages/gnome-xyz.scm

@@ -96,6 +96,41 @@ (define-public matcha-theme
     (home-page "https://github.com/vinceliuice/matcha")
     (license license:gpl3+)))
 
+(define-public arc-icon-theme
+  (package
+    (name "arc-icon-theme")
+    (version "20161122")
+    (source
+     (origin
+       (method git-fetch)
+       (uri (git-reference
+             (url "https://github.com/horst3180/arc-icon-theme")
+             (commit version)))
+       (file-name (git-file-name name version))
+       (sha256
+        (base32 "1ch3hp08qri93510hypzz6m2x4xgg2h15wvnhjwh1x1s1b7jvxjd"))))
+    (build-system gnu-build-system)
+    (arguments
+     `(#:phases
+       (modify-phases %standard-phases
+         (add-after 'unpack 'disable-configure-during-bootstrap
+           (lambda _
+             (substitute* "autogen.sh"
+               (("^\"\\$srcdir/configure\".*") ""))
+             #t)))))
+    (native-inputs
+     `(("autoconf" ,autoconf)
+       ("automake" ,automake)))
+    ;; When Arc is missing an icon, it looks in the Moka icon theme for it.
+    (propagated-inputs
+     `(("moka-icon-theme" ,moka-icon-theme)))
+    (synopsis "Arc icon theme")
+    (description "The Arc icon theme provides a set of icons matching the
+style of the Arc GTK theme.  Icons missing from the Arc theme are provided by
+the Moka icon theme.")
+    (home-page "https://github.com/horst3180/arc-icon-theme")
+    (license license:gpl3+)))
+
 (define-public delft-icon-theme
   (package
     (name "delft-icon-theme")

gnu/packages/gnome.scm

@@ -9626,41 +9626,6 @@ (define-public moka-icon-theme
     (license (list license:gpl3+
                    license:cc-by-sa4.0))))
 
-(define-public arc-icon-theme
-  (package
-    (name "arc-icon-theme")
-    (version "20161122")
-    (source
-     (origin
-       (method git-fetch)
-       (uri (git-reference
-             (url "https://github.com/horst3180/arc-icon-theme")
-             (commit version)))
-       (file-name (git-file-name name version))
-       (sha256
-        (base32 "1ch3hp08qri93510hypzz6m2x4xgg2h15wvnhjwh1x1s1b7jvxjd"))))
-    (build-system gnu-build-system)
-    (arguments
-     `(#:phases
-       (modify-phases %standard-phases
-         (add-after 'unpack 'disable-configure-during-bootstrap
-           (lambda _
-             (substitute* "autogen.sh"
-               (("^\"\\$srcdir/configure\".*") ""))
-             #t)))))
-    (native-inputs
-     `(("autoconf" ,autoconf)
-       ("automake" ,automake)))
-    ;; When Arc is missing an icon, it looks in the Moka icon theme for it.
-    (propagated-inputs
-     `(("moka-icon-theme" ,moka-icon-theme)))
-    (synopsis "Arc icon theme")
-    (description "The Arc icon theme provides a set of icons matching the
-style of the Arc GTK theme.  Icons missing from the Arc theme are provided by
-the Moka icon theme.")
-    (home-page "https://github.com/horst3180/arc-icon-theme")
-    (license license:gpl3+)))
-
 (define-public folks
   (package
     (name "folks")