Re-target for ES.Next (#3901)

A list of changes:
- 'es2015-subset' profile is deprecated, and an 'es.next' profile is added.
- The default profile is changed to 'es.next'
- Renamed the JERRY_ES2015 guard to JERRY_ESNEXT
- Renamed JERRY_ES2015_BUILTIN_* guards to JERRY_BUILTIN_*
- Moved es2015 specific tests to a new 'es.next' subdirectory
- Updated docs, targets, and test runners to reflect these changes

Resolves #3737.

JerryScript-DCO-1.0-Signed-off-by: Dániel Bátyai dbatyai@inf.u-szeged.hu

jerry-core/ecma/builtin-objects/ecma-builtin-array.c

@@ -65,7 +65,7 @@ ecma_builtin_array_object_is_array (ecma_value_t this_arg, /**< 'this' argument
   return ecma_is_value_array (arg);
 } /* ecma_builtin_array_object_is_array */
 
-#if ENABLED (JERRY_ES2015)
+#if ENABLED (JERRY_ESNEXT)
 /**
  * The Array object's 'from' routine
  *
@@ -473,7 +473,7 @@ ecma_builtin_array_species_get (ecma_value_t this_value) /**< This Value */
 {
   return ecma_copy_value (this_value);
 } /* ecma_builtin_array_species_get */
-#endif /* ENABLED (JERRY_ES2015) */
+#endif /* ENABLED (JERRY_ESNEXT) */
 
 /**
  * Handle calling [[Call]] of built-in Array object
@@ -500,9 +500,9 @@ ecma_builtin_array_dispatch_construct (const ecma_value_t *arguments_list_p, /**
 {
   JERRY_ASSERT (arguments_list_len == 0 || arguments_list_p != NULL);
 
-#if !ENABLED (JERRY_ES2015)
+#if !ENABLED (JERRY_ESNEXT)
   return ecma_op_create_array_object (arguments_list_p, arguments_list_len, true);
-#else /* ENABLED (JERRY_ES2015) */
+#else /* ENABLED (JERRY_ESNEXT) */
   ecma_object_t *proto_p = ecma_op_get_prototype_from_constructor (JERRY_CONTEXT (current_new_target),
                                                                    ECMA_BUILTIN_ID_ARRAY_PROTOTYPE);
 
@@ -523,7 +523,7 @@ ecma_builtin_array_dispatch_construct (const ecma_value_t *arguments_list_p, /**
   ECMA_SET_NON_NULL_POINTER (object_p->u2.prototype_cp, proto_p);
   ecma_deref_object (proto_p);
   return result;
-#endif /* ENABLED (JERRY_ES2015) */
+#endif /* ENABLED (JERRY_ESNEXT) */
 } /* ecma_builtin_array_dispatch_construct */
 
 /**