Simplify handling of multiple top-level nodes after parsing

spec/runtime/languages/arithmetic/errors.txt

@@ -3,7 +3,7 @@ recovers from errors at the top level
 =====================================================
 x * * y
 ---
-(ERROR '*')
+(expression (variable) (ERROR '*'))
 
 =====================================================
 recovers from errors inside parenthesized expressions
@@ -12,4 +12,4 @@ x + (y * + z) * 5
 ---
 (expression (sum
     (variable)
-    (product (group (ERROR '+')) (number))))
+    (product (group (ERROR '+')) (number))))

spec/runtime/languages/javascript/literals.txt

@@ -39,7 +39,7 @@ var x = {
             (statement_block (var_declaration (identifier) (identifier)))))))
 
 ==========================================
-parses comments
+parses comments z
 ==========================================
 // this is the beginning of the script.
 // here we go.

spec/runtime/languages/json/errors.txt

@@ -3,7 +3,7 @@ recovers from top-level errors
 ==========================================
 [}
 ---
-(ERROR '}')
+(value (ERROR <EOF>) (ERROR '}'))
 
 ==========================================
 recovers from unexpected tokens