Parse top-level macro invocations

Fixes atom/atom#18346

corpus/ambiguities.txt

@@ -163,3 +163,16 @@ int main() {
         (expression_statement (identifier))))
     (comment)
     (expression_statement (identifier)))))
+
+===============================================
+Top-level macro invocations
+===============================================
+
+DEFINE_SOMETHING(THING_A, "this is a thing a");
+DEFINE_SOMETHING(THING_B, "this is a thing b", "thanks");
+
+---
+
+(translation_unit
+  (call_expression (identifier) (argument_list (identifier) (string_literal)))
+  (call_expression (identifier) (argument_list (identifier) (string_literal) (string_literal))))

grammar.js

@@ -56,6 +56,7 @@ module.exports = grammar({
       $.function_definition,
       $.linkage_specification,
       $.declaration,
+      seq($.call_expression, ';'),
       $.type_definition,
       $._empty_declaration,
       $.preproc_if,

src/grammar.json

@@ -24,6 +24,19 @@
           "type": "SYMBOL",
           "name": "declaration"
         },
+        {
+          "type": "SEQ",
+          "members": [
+            {
+              "type": "SYMBOL",
+              "name": "call_expression"
+            },
+            {
+              "type": "STRING",
+              "value": ";"
+            }
+          ]
+        },
         {
           "type": "SYMBOL",
           "name": "type_definition"