Description:
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The report_mode variable set by mysqli_report() should be initialized in request init instead of global init to achieve a consistent behavior.

Test script:
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<?php
$mysqli = mysqli_connect();
mysqli_query($mysqli, "SEL");
?>


Expected result:
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No error message or exception.

Actual result:
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Nothing, error message or exception depending on mysqli_report() set by previous request in the same process.