Reland: Enable --harmony-function-tostring by default

Update tests to work with new behavior.

Thanks Yang Guo for fixing the GC problem in
ad126d46

R=adamk@chromium.org, machenbach@chromium.org
Q_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel

Bug: v8:4958
Change-Id: Ia7d9417f80087fb6df4ef877d0b4357875ee6c30
Reviewed-on: https://chromium-review.googlesource.com/834458Reviewed-by: Adam Klein <adamk@chromium.org>
Commit-Queue: Josh Wolfe <jwolfe@igalia.com>
Cr-Commit-Position: refs/heads/master@{#50486}

src/flag-definitions.h

@@ -211,7 +211,6 @@ DEFINE_IMPLICATION(harmony_class_fields, harmony_static_fields)
 
 // Features that are complete (but still behind --harmony/es-staging flag).
 #define HARMONY_STAGED(V)                                               \
-  V(harmony_function_tostring, "harmony Function.prototype.toString")   \
   V(harmony_restrict_constructor_return,                                \
     "harmony disallow non undefined primitive return value from class " \
     "constructor")                                                      \
@@ -225,6 +224,7 @@ DEFINE_IMPLICATION(harmony_class_fields, harmony_static_fields)
   V(harmony_regexp_named_captures, "harmony regexp named captures")     \
   V(harmony_regexp_property, "harmony Unicode regexp property classes") \
   V(harmony_async_iteration, "harmony async iteration")                 \
+  V(harmony_function_tostring, "harmony Function.prototype.toString")   \
   V(harmony_promise_finally, "harmony Promise.prototype.finally")
 
 #ifdef V8_INTL_SUPPORT

test/message/fail/paren_in_arg_string.out

-*%(basename)s:29: SyntaxError: Function arg string contains parenthesis
-var paren_in_arg_string_bad = new Function(')', 'return;');
+undefined:1: SyntaxError: Arg string terminates parameters early
+(function anonymous()
                     ^
-SyntaxError: Function arg string contains parenthesis
+SyntaxError: Arg string terminates parameters early
     at new Function (<anonymous>)
     at *%(basename)s:29:31

test/mjsunit/harmony/async-generators-basic.js

@@ -153,7 +153,7 @@ async function* asyncGeneratorForToString() {}
 assertEquals("async function* asyncGeneratorForToString() {}",
              asyncGeneratorForToString.toString());
 
-assertEquals("async function* () {}", async function*() {}.toString());
+assertEquals("async function*() {}", async function*() {}.toString());
 assertEquals("async function* namedAsyncGeneratorForToString() {}",
              async function* namedAsyncGeneratorForToString() {}.toString());
 
@@ -164,9 +164,9 @@ assertEquals("async *method() { }",
 assertEquals("async *method() { }",
              (new (class { async *method() { } })).method.toString());
 
-assertEquals("async function* anonymous() {\n\n}",
+assertEquals("async function* anonymous(\n) {\n\n}",
              AsyncGeneratorFunction().toString());
-assertEquals("async function* anonymous() {\n\n}",
+assertEquals("async function* anonymous(\n) {\n\n}",
              (new AsyncGeneratorFunction()).toString());
 
 // ----------------------------------------------------------------------------

test/mjsunit/regress/regress-2470.js

@@ -46,4 +46,4 @@ assertThrows('Function("a", "", "//", "//")', SyntaxError);
 // Some embedders rely on the string representation of the resulting
 // function in cases where no formal parameters are specified.
 var asString = Function("return 23").toString();
-assertSame("function anonymous() {\nreturn 23\n}", asString);
+assertSame("function anonymous(\n) {\nreturn 23\n}", asString);

test/mjsunit/regress/regress-crbug-109362.js

@@ -14,15 +14,16 @@ function test(expectation, f) {
 }
 
 /*
-(function() {
+(function(
+) {
 1 + reference_error //@ sourceURL=evaltest
 })
 */
-test("2:5", new Function(
+test("3:5", new Function(
     '1 + reference_error //@ sourceURL=evaltest'));
 /*
 (function(x
-/\**\/) {
+) {
 
  1 + reference_error //@ sourceURL=evaltest
 })
@@ -34,7 +35,7 @@ test("4:6", new Function(
 
 ,z//
 ,y
-/\**\/) {
+) {
 
  1 + reference_error //@ sourceURL=evaltest
 })
@@ -44,7 +45,7 @@ test("7:6", new Function(
 /*
 (function(x/\*,z//
 ,y*\/
-/\**\/) {
+) {
 1 + reference_error //@ sourceURL=evaltest
 })
 */

test/mjsunit/regress/regress-crbug-663410.js

@@ -4,5 +4,5 @@
 
 function alert(x) {};
 assertThrows(
-  Function("a=`","`,xss=1){alert(xss)")
+  'Function("a=`","`,xss=1){alert(xss)")'
 );

test/mozilla/mozilla.status

@@ -118,6 +118,10 @@
   # Invalid according to ES2015 syntax. (Details: crbug.com/726625)
   'ecma_3/extensions/regress-368516': [FAIL],
 
+  # Function.prototype.toString revision.
+  # (https://chromium-review.googlesource.com/c/546941#message-5dc0f5efe277388501e8870e39ec70383dfc7db8)
+  'js1_5/Scope/regress-185485': [FAIL],
+
   ##################### SKIPPED TESTS #####################
 
   # This test checks that we behave properly in an out-of-memory