Amber Heard: I'm Too Skinny for 'Justice League' -- Costume Fitting Rescheduled

Amber Heard never went to London for her costume fitting this week -- which is why her lawyers said she was unavailable for a deposition -- because she says the production crew felt she was too skinny, having lost 20 pounds because of what she says is overwhelming stress.

TMZ broke the story ... Johnny Depp's lawyer wanted to take her deposition in the domestic violence case, but ultimately the judge accepted the word of her legal team that she had to go to London for the fitting and would not get back until Thursday night ... the evening of the scheduled court hearing.

We got this pic of Amber in West Hollywood shot Wednesday, and turns out she never went to London. Her people say the trip was cancelled because the producers didn't think she was camera-ready for the role ... because of her weight.

Amber's team says they were never given proper notice, but Johnny's team says that's BS ... Amber's lawyers represented she was not in town, and she was.