Revert "[runtime] Make all built-in functions strict."

This reverts commit 72b88fda.

Reason for revert: Changes a layout test:
https://build.chromium.org/p/client.v8.fyi/builders/V8-Blink%20Linux%2064/builds/16595

Original change's description:
> [runtime] Make all built-in functions strict.
> 
> According to ES#sec-built-in-function-objects all built-in functions
> must be strict.
> 
> This is a preliminary CL before changing the way we define built-in
> functions in native JS files.
> 
> Bug: v8:6459
> Change-Id: I8e60b342f04ea1b0843fe1990334cbb9b26ebac4
> Reviewed-on: https://chromium-review.googlesource.com/546215
> Reviewed-by: Toon Verwaest <verwaest@chromium.org>
> Reviewed-by: Adam Klein <adamk@chromium.org>
> Commit-Queue: Igor Sheludko <ishell@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#46237}

TBR=adamk@chromium.org,ishell@chromium.org,verwaest@chromium.org

Change-Id: Ic458b478b2dd23aae7ea2a51aa6052c1f5931c56
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:6459
Reviewed-on: https://chromium-review.googlesource.com/549322Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46242}

src/factory.cc

@@ -1486,7 +1486,6 @@ Handle<JSFunction> Factory::NewFunction(Handle<Map> map,
   Handle<Context> context(isolate()->native_context());
   Handle<SharedFunctionInfo> info =
       NewSharedFunctionInfo(name, code, map->is_constructor());
-  // Proper language mode in shared function info will be set outside.
   DCHECK(is_sloppy(info->language_mode()));
   DCHECK(!map->IsUndefined(isolate()));
   DCHECK(
@@ -1505,10 +1504,8 @@ Handle<JSFunction> Factory::NewFunction(Handle<Map> map,
 
 
 Handle<JSFunction> Factory::NewFunction(Handle<String> name) {
-  Handle<JSFunction> result =
-      NewFunction(isolate()->sloppy_function_map(), name, MaybeHandle<Code>());
-  DCHECK(is_sloppy(result->shared()->language_mode()));
-  return result;
+  return NewFunction(
+      isolate()->sloppy_function_map(), name, MaybeHandle<Code>());
 }
 
 
@@ -1518,9 +1515,7 @@ Handle<JSFunction> Factory::NewFunctionWithoutPrototype(Handle<String> name,
   Handle<Map> map = is_strict
                         ? isolate()->strict_function_without_prototype_map()
                         : isolate()->sloppy_function_without_prototype_map();
-  Handle<JSFunction> result = NewFunction(map, name, code);
-  result->shared()->set_language_mode(is_strict ? STRICT : SLOPPY);
-  return result;
+  return NewFunction(map, name, code);
 }
 
 
@@ -1531,7 +1526,6 @@ Handle<JSFunction> Factory::NewFunction(Handle<String> name, Handle<Code> code,
                               : isolate()->sloppy_function_map();
   Handle<JSFunction> result = NewFunction(map, name, code);
   result->set_prototype_or_initial_map(*prototype);
-  result->shared()->set_language_mode(is_strict ? STRICT : SLOPPY);
   return result;
 }
 

src/js/collection.js

@@ -3,7 +3,6 @@
 // found in the LICENSE file.
 
 (function(global, utils) {
-
 "use strict";
 
 %CheckIsBootstrapping();

src/js/max-min.js

@@ -4,8 +4,6 @@
 
 (function(global, utils) {
 
-"use strict";
-
 %CheckIsBootstrapping();
 
 function MaxSimple(a, b) {

src/js/messages.js

@@ -6,8 +6,6 @@
 
 (function(global, utils) {
 
-"use strict";
-
 %CheckIsBootstrapping();
 
 // -------------------------------------------------------------------

src/js/spread.js

@@ -4,7 +4,7 @@
 
 (function(global, utils) {
 
-"use strict";
+'use strict';
 
 // -------------------------------------------------------------------
 // Imports

src/js/string.js

@@ -4,8 +4,6 @@
 
 (function(global, utils) {
 
-"use strict";
-
 %CheckIsBootstrapping();
 
 // -------------------------------------------------------------------

src/js/v8natives.js

@@ -4,8 +4,6 @@
 
 (function(global, utils) {
 
-"use strict";
-
 %CheckIsBootstrapping();
 
 // ----------------------------------------------------------------------------

test/mjsunit/function-caller.js

@@ -46,9 +46,11 @@ f(null);
 // Check called from eval.
 eval('f(null)');
 
-// Check called from builtin functions.
+// Check called from strict builtin functions.
 [null, null].sort(f);
 [null].forEach(f, null);
+
+// Check called from sloppy builtin functions.
 "abel".replace(/b/g, function h() {
-   assertEquals(null, h.caller);
+   assertEquals(String.prototype.replace, h.caller);
 });

test/mjsunit/fuzz-accessors.js

@@ -26,11 +26,7 @@
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 var builtInPropertyNames = [
-  'prototype', 'length', 0, 1, '$1', 'name', 'message', 'constructor'
-];
-
-var builtInPropertyNamesMayThrow = [
-  'caller', 'arguments'
+  'prototype', 'length', 'caller', 0, 1, '$1', 'arguments', 'name', 'message', 'constructor'
 ];
 
 function getAnException() {
@@ -81,13 +77,6 @@ function runTest(fun) {
         var propertyName = builtInPropertyNames[k];
         fun(obj, propertyName);
       }
-      for (var k in builtInPropertyNamesMayThrow) {
-        var propertyName = builtInPropertyNamesMayThrow[k];
-        try {
-          fun(obj, propertyName);
-        } catch (e) {
-        }
-      }
     }
   }
 }

test/mjsunit/harmony/async-from-sync-iterator.js

@@ -625,11 +625,6 @@ if (testFailed) {
 }
 
 (function ExtractedAsyncFromSyncIteratorMethods() {
-  // TODO(ishell, caitp): Rewrite the test without using function.caller.
-  // According to ES#sec-built-in-function-objects all built-in functions
-  // must be strict. And ES#sec-forbidden-extensions states that the value of
-  // a function.caller must not be a strict function.
-  return;
   // Async-from-Sync iterator methods can be extracted via function.caller.
   // TODO(caitp): test extracted `throw` method using yield* in async generator.
   let extractor = [0, 1, 2, 3, 4,5,6,7,8,9];

test/mjsunit/regress/regress-682349.js

@@ -6,7 +6,7 @@
 
 let success = false;
 function f() {
-  success = (f.caller === null);
+  success = (f.caller.arguments === null);
 }
 Promise.resolve().then(f);
 %RunMicrotasks();

test/mjsunit/test-native-method-names.js

@@ -12,9 +12,6 @@ function CheckMethodEx(object, prop_name, function_name, length) {
   assertTrue(desc.configurable);
   assertTrue(desc.writable);
   assertThrows(() => new desc.value());
-  // Check that built-in function is strict.
-  assertThrows(() => desc.value.arguments);
-  assertThrows(() => desc.value.caller);
 }
 
 function CheckMethod(object, name, length) {
@@ -35,9 +32,6 @@ function CheckGetter(object, name) {
   assertEquals(0, desc.get.length);
   assertFalse(desc.enumerable);
   assertTrue(desc.configurable);
-  // Check that built-in function is strict.
-  assertThrows(() => desc.get.arguments);
-  assertThrows(() => desc.get.caller);
 }