Discharge risk of an LED fade-in circuit
There is no danger to the LED from removing the voltage source V1 or shorting it to ground. The LED itself limits the voltage across the capacitor, i.e. if it was safe while the voltage source was still connected, it's also at least as safe after it has been disconnected.
However, if you allow C1 to charge up to greater than the LED forward voltage and then connect the LED across it you could quite well damage the LED.