[revert] remove Statusbar marginTop for navTransparent

[bang9]

• revert add Statusbar marginTop for navTransparent #3212

Reason

Status bar can be overlay to screen(app will draw under the status bar), It is not odd behavior..
Transplucent status bar is default in iOS(cli, expo) and Android(expo)
But not default option on Android(cli), it just can be set by translucent of 'StatusBar'

If user want to status bar overlay to screen, they must use 'SafeAreaView' but this working only in iOS, because that concept doesn't exist on Android.
for this reason, not margin top to navigation in RNRF but padding top to screen(or wrapping routes with OverlayStatusBarView) by user self

please see the example code

import {SafeAreaView, StatusBar, Platform } from 'react-native';

const OverlayStatusBarView = (props) => {
    const {children, style, ...rest} = props;
    return(
      <SafeAreaView 
        style={[{paddingTop: StatusBar.currentHeight},style]}
        {...rest}
      >
        <StatusBar translucent /> 
        {children}
      </SafeAreaView>
    )
}

[aksonov]

I can't merge this ticket because it brakes existing apps (on iOS). Probably you can add check for iOS/Android and set/not set height depends from ios..

[bang9]

I can't merge this ticket because it brakes existing apps (on iOS). Probably you can add check for iOS/Android and set/not set height depends from ios..

@aksonov It only affect to android
StatusBar.currentHeight is always return 0 on iOS