Yes, it just basically folds together the first two dimensions, the third will stay unaffected.
Example output from my code:
out
Variable containing:
( 0 ,.,.) = 
  0.0426 -0.2047 -0.0125  ...  -0.0409  0.1487  0.0376
 -0.0744 -0.0927  0.0185  ...  -0.1620  0.1348 -0.2179
  0.0111 -0.1565 -0.0192  ...  -0.1247  0.0352 -0.0625

( 1 ,.,.) = 
  0.0726 -0.1911  0.3049  ...  -0.1031  0.1991  0.0659
 -0.2233  0.1622  0.0794  ...  -0.1720  0.1020 -0.0430
  0.0600 -0.3536  0.0201  ...  -0.0990 -0.1203 -0.1207

( 2 ,.,.) = 
  0.0000  0.0000  0.0000  ...   0.0000  0.0000  0.0000
 -0.1225  0.1387  0.1205  ...  -0.1052 -0.1638 -0.2314
  0.0336 -0.3169  0.0090  ...  -0.0343  0.0635 -0.0280

( 3 ,.,.) = 
  0.0000  0.0000  0.0000  ...   0.0000  0.0000  0.0000
  0.0001 -0.1604  0.1111  ...  -0.0778 -0.1291 -0.0852
  0.0000  0.0000  0.0000  ...   0.0000  0.0000  0.0000
[torch.FloatTensor of size 4x3x128]

out.view(-1, out.size(2))
Variable containing:
 0.0426 -0.2047 -0.0125  ...  -0.0409  0.1487  0.0376
-0.0744 -0.0927  0.0185  ...  -0.1620  0.1348 -0.2179
 0.0111 -0.1565 -0.0192  ...  -0.1247  0.0352 -0.0625
          ...             ⋱             ...          
 0.0000  0.0000  0.0000  ...   0.0000  0.0000  0.0000
 0.0001 -0.1604  0.1111  ...  -0.0778 -0.1291 -0.0852
 0.0000  0.0000  0.0000  ...   0.0000  0.0000  0.0000
[torch.FloatTensor of size 12x128]