Merge r174260 - Change how 32-bit JSValues check if they are a Boolean

Rubber stamped by Filip Pizlo.

32-bit JSValue::isBoolean can simply check if its tag corresponds
to the boolean tag instead of checking if it's either true or false.

* runtime/JSCJSValueInlines.h:
(JSC::JSValue::isBoolean):

Canonical link: https://commits.webkit.org/154760.101@webkitgtk/2.6
git-svn-id: https://svn.webkit.org/repository/webkit/releases/WebKitGTK/webkit-2.6@174953 268f45cc-cd09-0410-ab3c-d52691b4dbfc

Source/JavaScriptCore/ChangeLog

@@ -1,3 +1,15 @@
+2014-10-03  Saam Barati  <saambarati1@gmail.com>
+
+        Change how 32-bit JSValues check if they are a Boolean
+
+        Rubber stamped by Filip Pizlo.
+
+        32-bit JSValue::isBoolean can simply check if its tag corresponds 
+        to the boolean tag instead of checking if it's either true or false.
+
+        * runtime/JSCJSValueInlines.h:
+        (JSC::JSValue::isBoolean):
+
 2014-10-01  Anders Carlsson  <andersca@apple.com>
 
         Use variadic templates for jsMakeNontrivialString

Source/JavaScriptCore/runtime/JSCJSValueInlines.h

@@ -327,7 +327,7 @@ inline bool JSValue::isNumber() const
 
 inline bool JSValue::isBoolean() const
 {
-    return isTrue() || isFalse();
+    return tag() == BooleanTag;
 }
 
 inline bool JSValue::asBoolean() const