Yes, it is part of DST determination
Time is a quite arbitrary concept (along with time zones and standard time zones and daylight savings time zones).
Prior to the 19th century or there about, a day started when it was light enough to see and when one felt tired and could no longer see the sun. Man got tired, went to sleep (and hoped they would wake up again). The location of the Terminator (sunrise sunset line and astronomical mechanics decided when you should be awake and feed the cows and pigs. ( With App Inventor, see the Terminator tutorial )
The most arbitrary of concepts might be DST (see the articles in How Are Time Zones Decided? ).
Where and when DST is observed is entirely serendipity. If you want to know where the earth in anyplace is in sunlight or not (assuming no clouds or smog), determine the sun's position.
The LocationSensor and the Clock (System Time) work together to attempt to identify what time zone an Android is in and provide information about whether the device is using standard or daylight savings time. When you are connected to a mobile network, the date and time will be set automatically. This may mean that the indication you get for DST may be determined by where your phone service provider is located, not your device location. 
Where does Android get time from?
A time signal from a network time server ( provided by your phone service carrier, not necessarily Google) might be used to set the Android device's system clock if automatic time detection is supported on the device and the time detector service is configured to use it. Android uses the network time origin as the primary automatic time detection origin by default.
Network time detection | Android Open Source Project.
Reading a lot of articles about DST I believe there isn't any 'official' source for knowing when DST is locally in force. Your phone makes its best efforts and web sites try to collect the best information available and frequently that information is not up to date. So why do we have a discussion about whether the information about the timeanddate. com information is valid?