Roll src/third_party/harfbuzz-ng/src/ 6ad3fcdda..59345cdef (5 commits)

https://chromium.googlesource.com/external/github.com/harfbuzz/harfbuzz.git/+log/6ad3fcddaf2b..59345cdef38c

$ git log 6ad3fcdda..59345cdef --date=short --no-merges --format='%ad %ae %s'
2018-12-06 ariza [CFF] Refix oss-fuzz 11714: set_blends (PR #1458) (#1460)
2018-12-06 behdad Fix likely check
2018-12-06 behdad Add default value to first argument of sub_array()
2018-12-06 behdad Add sub_array to hb_vector_t
2018-12-06 behdad Add default-value for second arg of sub_array()

Created with:
  roll-dep src/third_party/harfbuzz-ng/src
R=bashi@chromium.org,behdad@chromium.org,behdad@google.com,drott@chromium.org,eae@chromium.org,jshin@chromium.org

Change-Id: I43da06c24f22509b8ad010191c630e833a15a235
Reviewed-on: https://chromium-review.googlesource.com/c/1368044
Commit-Queue: Emil A Eklund <eae@chromium.org>
Reviewed-by: Emil A Eklund <eae@chromium.org>
Cr-Commit-Position: refs/heads/master@{#614759}

DEPS

@@ -170,7 +170,7 @@ vars = {
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling HarfBuzz
   # and whatever else without interference from each other.
-  'harfbuzz_revision': '6ad3fcddaf2ba8ebc9ad49ff9e7b33b60fcad16a',
+  'harfbuzz_revision': '59345cdef38cf1f514a6a0eb6e8852350acb6166',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling catapult
   # and whatever else without interference from each other.

third_party/harfbuzz-ng/README.chromium

 Name: harfbuzz-ng
 Short Name: harfbuzz-ng
 URL: http://harfbuzz.org
-Version: 2.2.0-293
-Date: 20181206
-Revision: 6ad3fcddaf2ba8ebc9ad49ff9e7b33b60fcad16a
+Version: 2.2.0-298
+Date: 20181207
+Revision: 59345cdef38cf1f514a6a0eb6e8852350acb6166
 Security Critical: yes
 License: MIT
 License File: src/COPYING