For the grilled salmon and corn:
1. Spray the grill grate with nonstick cooking spray and then preheat the grill to medium-high.
2. Lightly spray the corn cobs with nonstick cooking spray, then season the corn and salmon fillets with salt and pepper.
3. Grill the salmon on both sides until it is cooked through, about 4 to 6 minutes per side, depending on the thickness of the fillet. Grill the corn until tender and golden about 6 to 8 minutes total for all sides, turning every few minutes. Transfer the salmon and corn to a cutting board and let cool.
(The salmon and corn can be grilled in advance and stored in the refrigerator for up to 3 days.)
For the green salad:
1. Slice the salmon into strips and place them in a mixing bowl. Cut the corn from the cob and add the kernels to the bowl. Add the mushroom slices and half of the vinaigrette. Toss to coat the salmon and vegetables.
2. Place the romaine in a separate salad bowl and toss it with the remaining vinaigrette. Arrange the salmon, corn and mushroom mixture on top.