Split after an opening bracket if named assigns

When we intentionally split each argument because of a named assignment, then
also split after the opening bracket (before the first argument). This makes
things a bit nicer to look at. It also allows one to rename the function
without having to reformat all of the arguments to the function call.
diff --git a/CHANGELOG b/CHANGELOG
index 30f807d..7dfea27 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -8,6 +8,11 @@
   DEDENT_CLOSING_BRACKETS is set.
 - Don't count "pylint" directives as exceeding the column limit.
 
+### Changed
+- We split all of the arguments to a function call if there's a named argument.
+  In this case, we want to split before the opening bracket too. This makes
+  things look a bit better.
+
 ### Fixed
 - When retaining format of a multiline string with Chromium style, make sure
   that the multiline string doesn't mess up where the following comma ends up.