Fix: do not use incorrect shortcut for double.

Author: fangerer

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/nodes/util/CoerceToStringNode.java

@@ -43,7 +43,6 @@
 import static com.oracle.graal.python.builtins.PythonBuiltinClassType.TypeError;
 
 import com.oracle.graal.python.builtins.PythonBuiltinClassType;
-import com.oracle.graal.python.builtins.objects.floats.PFloat;
 import com.oracle.graal.python.nodes.PGuards;
 import com.oracle.graal.python.nodes.PNodeWithContext;
 import com.oracle.graal.python.nodes.PRaiseNode;
@@ -96,11 +95,6 @@ static String doLong(long x) {
         return Long.toString(x);
     }
 
-    @Specialization
-    static String doDouble(double x) {
-        return PFloat.doubleToString(x);
-    }
-
     @Specialization
     static Object doGeneric(VirtualFrame frame, Object x,
                     @Cached("create(__STR__)") LookupAndCallUnaryNode callStrNode,