FramebufferTest: fix read overruns in glTexImage2D upload The dimensions specified in glTexImage2D did not match the size of the arrays of pixels. This was tripping AddressSanitizer, which noticed it was reading past the end of the arrays. Bug: angleproject:4737 Bug: angleproject:6600 Change-Id: Ie9e1705136a4b7f853b3a897e3c294c953c475f6 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3235904 Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org> Reviewed-by: Jamie Madill <jmadill@chromium.org> Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org>