[gtksourceview/gtksourceview-4-6] cpp.lang: add keywords for coroutines (C++20)

[Christian Hergert <chergert src gnome org>]

commit 046e98603cc8f2ba8e46d9c0a78fc85dadff1ddb
Author: Elias Aebi <eyelash users noreply github com>
Date:   Thu Mar 5 13:32:03 2020 +0100

    cpp.lang: add keywords for coroutines (C++20)

 data/language-specs/cpp.lang | 3 +++
 1 file changed, 3 insertions(+)
---
diff --git a/data/language-specs/cpp.lang b/data/language-specs/cpp.lang
index 51ad637b..ff63f3b8 100644
--- a/data/language-specs/cpp.lang
+++ b/data/language-specs/cpp.lang
@@ -60,6 +60,9 @@
                     <keyword>consteval</keyword>
                     <keyword>constexpr</keyword>
                     <keyword>const_cast</keyword>
+                    <keyword>co_await</keyword>
+                    <keyword>co_return</keyword>
+                    <keyword>co_yield</keyword>
                     <keyword>decltype</keyword>
                     <keyword>delete</keyword>
                     <keyword>dynamic_cast</keyword>