For those of you who have mixed it up over the years you would have realised that cardio before weight training reduces the amount of training volume you can perform in your sets. Several studies have also been done to support this and show that weight training before cardio may not even negatively affect improvements in endurance to a significant degree. (See Research Here)
In one particular study, cardio before weight training resulted in a 9.1–18.6% decrease in total reps performed: (See Study Here)
Training volume (Reps*Sets*Weight and TUT) is the main driver of muscle growth, so a significant reduction in reps performed often appears to decrease muscle growth which is not ideal if you are trying to tone or bulk.
Basically, if you regularly lift weights and perform cardio in one training session, weights should come first. By doing this, you'll be able to train with sufficient volume and effectively improve endurance.