Roll buildtools/third_party/libunwind/trunk/ 49191c55b..012c3438e (3 commits)

https://chromium.googlesource.com/external/github.com/llvm/llvm-project/libunwind.git/+log/49191c55bba0..012c3438e079

Created with:
  roll-dep buildtools/third_party/libunwind/trunk

Change-Id: I3b7a98c199af7919f8d0da1630848017e17fa3d3
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/95891
Commit-Queue: Nigi <nigi@chromium.org>
Reviewed-by: Nigi <nigi@chromium.org>
diff --git a/DEPS b/DEPS
index 1b82a92..ad86381 100644
--- a/DEPS
+++ b/DEPS
@@ -110,7 +110,7 @@
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling libunwind
   # and whatever else without interference from each other.
-  'libunwind_revision': '49191c55bba0e64664954eec93a43d8eb11e5798',
+  'libunwind_revision': '012c3438e0795fa6ad1626f1f5e1c0ab577b91f6',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling markupsafe
   # and whatever else without interference from each other.