Better error message for mismatched parameter names between message and translation

pkg/intl/CHANGELOG.md

Index: pkg/intl/CHANGELOG.md
diff --git a/pkg/intl/CHANGELOG.md b/pkg/intl/CHANGELOG.md
index b1ba3586f3d702f8bcca7de38fe21b0542743d0a..ca7920ea4c33b62053ba4e46aca62913ddad338b 100644
--- a/pkg/intl/CHANGELOG.md
+++ b/pkg/intl/CHANGELOG.md
@@ -3,6 +3,10 @@
     is DateFormat.parseUtc, but the parseUTC variant is still retained
     for backward-compatibility.
 
+  * Provide a better error message when generating translated versions
+    and the name of a variable substitution in the message doesn't
+    match the name in the translation.
+
 ## 0.11.9
   * Fix bug with per-mille parsing (only divided by 100, not 1000)