Merge V8 at 3.8.9.11

Bug: 5688872

Change-Id: Ie3b1dd67a730ec5e82686b7b37dba26f6a9bb24f
diff --git a/src/macros.py b/src/macros.py
index bf7119f..8e9c62d 100644
--- a/src/macros.py
+++ b/src/macros.py
@@ -26,7 +26,7 @@
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 # Dictionary that is passed as defines for js2c.py.
-# Used for defines that must be defined for all native js files.
+# Used for defines that must be defined for all native JS files.
 
 const NONE        = 0;
 const READ_ONLY   = 1;
@@ -101,6 +101,9 @@
 macro IS_ARRAY(arg)             = (%_IsArray(arg));
 macro IS_FUNCTION(arg)          = (%_IsFunction(arg));
 macro IS_REGEXP(arg)            = (%_IsRegExp(arg));
+macro IS_SET(arg)               = (%_ClassOf(arg) === 'Set');
+macro IS_MAP(arg)               = (%_ClassOf(arg) === 'Map');
+macro IS_WEAKMAP(arg)           = (%_ClassOf(arg) === 'WeakMap');
 macro IS_DATE(arg)              = (%_ClassOf(arg) === 'Date');
 macro IS_NUMBER_WRAPPER(arg)    = (%_ClassOf(arg) === 'Number');
 macro IS_STRING_WRAPPER(arg)    = (%_ClassOf(arg) === 'String');