p-calendar treats utc="false" incorrectly, and converts date to UTC on selection

[nieldw]

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Plunkr Case (Bug Reports)
https://plnkr.co/edit/dICdEA?p=preview

Current behavior
Without the "utc" property, or with the property without a value, the calendar interprets the date selected in local time. With the "utc" property, regardless of the value, the calendar interprets the date selected in UTC. The default, not setting the property, does not behave the same as setting "utc=false", which is supposed to be the same as the default.

Expected behavior
Setting "utc=false" should make the calendar interpret the date selected in local time.

Minimal reproduction of the problem with instructions

    <div style="display: grid; grid-template-columns: 1fr 1fr 1fr; grid-column-gap: 10px;">
      <span></span><span>Local time</span><span>UTC</span>
      <p-calendar [readonlyInput]="true" required name="cal3" [(ngModel)]="cal3Date" utc="true"></p-calendar>
      <span>{{ cal3Date }}</span>
      <span>{{ cal3Date.toISOString() }}</span>
    </div>

Select a date. The selected date is not midnight in local time.

What is the motivation / use case for changing the behavior?
UTC behavior is confusing for users. For example, see #2426 ("Calendar selected date is off a day").
This is possibly also related to #4359

Please tell us about your environment:
Plunker.

• Angular version: 4.2.6

• PrimeNG version: 5.0.2

• Browser: [Chrome 63 | Firefox 58]

[cagataycivici]

Should be [utc]="false", in Angular use [] for booleans and numbers. Otherwise it will be string.