get Google APIKey
Retrieves the Google API key set using setGoogleAPIKey
Return
The Google API key or an empty string if it hasn't been set yet
Throws
if the SDK hasn't been initialized (by invoking initialize)
Retrieves the Google API key set using setGoogleAPIKey
The Google API key or an empty string if it hasn't been set yet
if the SDK hasn't been initialized (by invoking initialize)