Use setTimeZone if this method exists.

The php version is not a critical factor to choose the method, but we have to use setTimeZone, if it exists.
merged branch dropfen/master (PR #9015)

This PR was submitted for the master branch but it was merged into the 2.2 branch instead (closes #9015).

Discussion
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Fix #6029 : Use setTimeZone if this method exists.

The php version is not a critical factor to choose the method, but we have to use setTimeZone, if it exists.

Commits
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7d84cd7 Use setTimeZone if this method exists.
removed unneeded comment