QJSEngine::evaluate() incorrectly evaluates logic inside if statements.

"1<1" does not return the same value as "1<1?true:false".

When comparing numeric literals X and Y, the operators <, >, <=, and >= seem to always give the right answer except for when X == Y and both are non-negative.

These operators all behave correctly on their own (e.g. "1<1" returns false).
However, inside a regular "if" statement or a ternary operator they
behave as described above, evaluating incorrectly when comparing a number to
itself (e.g. "if(1<1){true;}else{false;}" and "1<1?true:false" both return true).

The following unit test demonstrates the bug. It passes in versions prior to 5.11.0 and fails in all versions since 5.11.0.  (Tested versions include 5.6.2, 5.7.0, 5.9.0, 5.10.0, 5.10.1, 5.11.0, 5.11.1, 5.12.1)

void tst_QJSEngine::logicError()
{
    QJSEngine engine;
    QJSValue value =
        engine.evaluate("( 0 < 0 ) ? 'WRONG ANSWER' : 'RIGHT ANSWER'");
    QVERIFY(!value.isError());
    QCOMPARE(value.toString(), "RIGHT ANSWER");
}