Add missing specialization to 'AsPythonObjectNode'.

Author: fangerer

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/objects/cext/CExtNodes.java

@@ -406,6 +406,11 @@ String doString(String object) {
             return object;
         }
 
+        @Specialization
+        boolean doBoolean(boolean b) {
+            return b;
+        }
+
         @Specialization
         byte doLong(byte b) {
             return b;