gnu: Add rust-markup5ever-0.12.

* gnu/packages/crates-io.scm (rust-markup5ever-0.12): New variable.
(rust-markup5ever-0.11): Inherit from rust-markup5ever-0.12.

Change-Id: Ieb3cd806b1155e169314e2bf3b05adbdad95079a
Signed-off-by: Efraim Flashner <efraim@flashner.co.il>

gnu/packages/crates-io.scm

@@ -40958,8 +40958,35 @@ template engine for Rust.")
      "This package provides a fast, type-safe template engine for Rust.")
     (license (list license:expat license:asl2.0))))
 
+(define-public rust-markup5ever-0.12
+  (package
+    (name "rust-markup5ever")
+    (version "0.12.1")
+    (source (origin
+              (method url-fetch)
+              (uri (crate-uri "markup5ever" version))
+              (file-name (string-append name "-" version ".tar.gz"))
+              (sha256
+               (base32
+                "0idy4vjihg2dw73j2vkb5kdghvga3bwnw0qx8jwci4m6xfxkmkhn"))))
+    (build-system cargo-build-system)
+    (arguments
+     `(#:cargo-inputs
+       (("rust-log" ,rust-log-0.4)
+        ("rust-phf" ,rust-phf-0.11)
+        ("rust-phf-codegen" ,rust-phf-codegen-0.11)
+        ("rust-string-cache" ,rust-string-cache-0.8)
+        ("rust-string-cache-codegen" ,rust-string-cache-codegen-0.5)
+        ("rust-tendril" ,rust-tendril-0.4))))
+    (home-page "https://github.com/servo/html5ever")
+    (synopsis "Common code for xml5ever and html5ever")
+    (description
+     "Common code for xml5ever and html5ever.")
+    (license (list license:expat license:asl2.0))))
+
 (define-public rust-markup5ever-0.11
   (package
+    (inherit rust-markup5ever-0.12)
     (name "rust-markup5ever")
     (version "0.11.0")
     (source (origin
@@ -40969,7 +40996,6 @@ template engine for Rust.")
               (sha256
                (base32
                 "05mhzsp6lfxla1fgd0ac283b405s6kyj27wj5r6d7wq42jxjj9ks"))))
-    (build-system cargo-build-system)
     (arguments
      `(#:cargo-inputs
        (("rust-log" ,rust-log-0.4)
@@ -40977,12 +41003,7 @@ template engine for Rust.")
         ("rust-phf-codegen" ,rust-phf-codegen-0.10)
         ("rust-string-cache" ,rust-string-cache-0.8)
         ("rust-string-cache-codegen" ,rust-string-cache-codegen-0.5)
-        ("rust-tendril" ,rust-tendril-0.4))))
-    (home-page "https://github.com/servo/html5ever")
-    (synopsis "Common code for xml5ever and html5ever")
-    (description
-     "Common code for xml5ever and html5ever.")
-    (license (list license:expat license:asl2.0))))
+        ("rust-tendril" ,rust-tendril-0.4))))))
 
 (define-public rust-markup5ever-0.10
   (package