SkRemoteGlyphCache: Make serialization code bitness agnostic.
SkRemoteGlyphCache: Make serialization code bitness agnostic.

With this change we use the same serialization regardless of whether
we are targeting a 32-bit or a 64-bit machine.

Bug: chromium:865796, chromium:880617, chromium:879123
Change-Id: Ia8e5757a4e8e3986041e30827eaaa154595c37ba
Reviewed-on: https://skia-review.googlesource.com/141606
Auto-Submit: Peter Collingbourne <0a9c5350547d97e930a976072b24aa4bbddb3981@google.com>
Commit-Queue: Mike Klein <14574f09dfa9b4e14759b88c3426a495a0e627b0@google.com>
Reviewed-by: Khusal Sagar <7c3e7b6b198ace4145f09ef7c4cf18c84ce8661e@chromium.org>

rubenvb/skia,aosp-mirror/platform_external_skia,HalCanary/skia-hc,google/skia,google/skia,google/skia,Hikari-no-Tenshi/android_external_skia,google/skia,Hikari-no-Tenshi/android_external_skia,rubenvb/skia,google/skia,HalCanary/skia-hc,google/skia,google/skia,rubenvb/skia,Hikari-no-Tenshi/android_external_skia,aosp-mirror/platform_external_skia,rubenvb/skia,HalCanary/skia-hc,rubenvb/skia,google/skia,HalCanary/skia-hc,rubenvb/skia,HalCanary/skia-hc,aosp-mirror/platform_external_skia,Hikari-no-Tenshi/android_external_skia,rubenvb/skia,HalCanary/skia-hc,aosp-mirror/platform_external_skia,rubenvb/skia,rubenvb/skia,HalCanary/skia-hc,aosp-mirror/platform_external_skia,Hikari-no-Tenshi/android_external_skia,Hikari-no-Tenshi/android_external_skia,google/skia,google/skia,aosp-mirror/platform_external_skia,aosp-mirror/platform_external_skia,HalCanary/skia-hc,Hikari-no-Tenshi/android_external_skia,HalCanary/skia-hc,Hikari-no-Tenshi/android_external_skia,aosp-mirror/platform_external_skia,rubenvb/skia,aosp-mirror/platform_external_skia,aosp-mirror/platform_external_skia,HalCanary/skia-hc