Re-generate StylClangFormatStyleOptions.rst

Author: Galen Elias

clang/docs/ClangFormatStyleOptions.rst

@@ -2088,6 +2088,12 @@ the configuration (without a prefix: ``Auto``).
   If ``true``, ``while (true) continue;`` can be put on a single
   line.
 
+.. _AllowShortNamespacesOnASingleLine:
+
+**AllowShortNamespacesOnASingleLine** (``Boolean``) :versionbadge:`clang-format 20` :ref:`¶ <AllowShortNamespacesOnASingleLine>`
+  If ``true``, ``namespace a { class b; }`` can be put on a single a single
+  line.
+
 .. _AlwaysBreakAfterDefinitionReturnType:
 
 **AlwaysBreakAfterDefinitionReturnType** (``DefinitionReturnTypeBreakingStyle``) :versionbadge:`clang-format 3.7` :ref:`¶ <AlwaysBreakAfterDefinitionReturnType>`