Prior to the Trials of Gnomus update you would receive a phone call telling you about the Golden Gnomes and then would need to discover a certain number of Golden Gnomes to trigger the second phone call where the Gnomes would congratulate you and provide you with the bomb to unlock the passage to the Chamber of the Gnomes.
From what they discussed in one of the "Live from Popcap" streams just after the Trials of Gnomus update launched one of the things which occurred besides Town Hall opening and Rux's shop finishing its remodel is that they opened the passage to the Chamber of Gnomes for everyone.
That being the case it is also likely that the second phone call was removed since the entire sequence associated with it, receiving the bomb and figuring out where to place it, was no longer necessary since the secret passage is now supposed to be open by default. Whether or not they remembered to change the original message in the first phone call is another matter entirely; having done that months ago I have no way to go back and check.
