A DESCRIPTION OF THE PROBLEM :
TimeZone.getTimeZone(null) should fallback to default timezone (GMT) without causing NPE

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Make this call:

TimeZone.getTimeZone(null)

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Fallback Timezone GTM should be returned.
ACTUAL -
NPE is thrown.

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TimeZone.getTimeZone(null)
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