Description:
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If you do setlocale("estonia") on a windows machine then json_encode outputs floats with commas which will cause a parse error in all browsers. It should output dots

Reproduce code:
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setlocale("estonia");
json_encode(array('float_test'=>10.12345));

Expected result:
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{"float_test": 10.12345}

Actual result:
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{"float_test": 10,12345}