Bump to mono/2017-12/de4729fa

jonpryor · jonpryor · commit fc953c8963dc · 2018-02-21T08:03:44.000-05:00
Context: dotnet#1078 Context: mono/mono#7145 The primary impetus is that mono/de4729fa contains "ignore" improvements to `mono-api-html`, which will be needed in order to complete PR dotnet#1078.
diff --git a/external/mono b/external/mono
@@ -1 +1 @@
-Subproject commit 0d51a8063beb25da3f4390a9ffddb231e3776a89
+Subproject commit de4729fae29dffd358fb96e3b6d367ca6b1e507a
