test: make func source test compatbile with v12

The string stored in V8 with the function source code is different on
v12. Update the regexp used in our test to match older and newer
versions.

PR-URL: #326
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>

test/plugin/inspect-test.js

@@ -48,11 +48,9 @@ const hashMapTests = {
         // Include 'source:' and '>' to act as boundaries. (Avoid
         // passing if the whole file it displayed instead of just
         // the function we want.)
-        const arrowSource = 'source:\n' +
-            'function c.hashmap.(anonymous function)(a,b)=>{a+b}\n' +
-            '>';
+        const arrowSource = /source:\nfunction c.hashmap.(\(anonymous function\)|<computed>)\(a,b\)=>{a\+b}\n>/;
 
-        t.ok(lines.includes(arrowSource),
+        t.ok(lines.match(arrowSource),
             'hashmap[25] should have the correct function source');
         cb(null);
       });