Make SK_API visible to user config file

TODO(kjlubick) Revert this after [1] is cleaned up

[1] https://source.chromium.org/chromium/chromium/src/+/main:skia/config/SkUserConfig.h;l=151;drc=a0085bcf955983d9e0aace9755c8b5b7ad5bea36

Change-Id: I9929fc94ccb270758a82772604fbf3d1a8de1018
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/631776
Reviewed-by: Florin Malita <fmalita@google.com>
1 file changed