Remove use of hb_subset_input_set_drop_layout() from SkPDFSubsetFont.cpp
Remove use of hb_subset_input_set_drop_layout() from SkPDFSubsetFont.cpp

Remove the calling of a deprecated HarfBuzz function. The current use of
HarfBuzz's subsetter calls a deprecated symbol:
hb_subset_input_set_drop_layout(). The change with the deprecation can
be found at [1]. Instead, HarfBuzz disables layout by default, as
indicated by the comment found at [2], rendering the calling of the
function unnecessary in Skia.

[1] https://github.com/harfbuzz/harfbuzz/commit/0ff3618c2d841d16cce9ba2d73321048e7ca6a2d?diff=split#diff-e34a949604c500d3a2aeaafa06cf7d96L142

[2] https://github.com/harfbuzz/harfbuzz/blob/master/src/hb-subset-input.cc#L55

Bug: chromium:931719
Change-Id: I530e2257d49a6aeb2164bdc2a0358a998d62591f
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/221411
Commit-Queue: Ben Wagner <53965154ffeecc4a10886eab9259e95965f2979a@google.com>
Reviewed-by: Hal Canary <fd9641b23487c8ee78406c27513624c460600766@google.com>

aosp-mirror/platform_external_skia,google/skia,aosp-mirror/platform_external_skia,aosp-mirror/platform_external_skia,HalCanary/skia-hc,google/skia,HalCanary/skia-hc,aosp-mirror/platform_external_skia,aosp-mirror/platform_external_skia,aosp-mirror/platform_external_skia,google/skia,google/skia,google/skia,HalCanary/skia-hc,HalCanary/skia-hc,HalCanary/skia-hc,google/skia,aosp-mirror/platform_external_skia,HalCanary/skia-hc,google/skia,aosp-mirror/platform_external_skia,aosp-mirror/platform_external_skia,aosp-mirror/platform_external_skia,HalCanary/skia-hc,google/skia,HalCanary/skia-hc,HalCanary/skia-hc,google/skia,google/skia,HalCanary/skia-hc