Revert "Remove memory used by unique glyphs"

This reverts commit 7d20bc42f45330104bfa603047e6d032130f9688.

Reason for revert: <INSERT REASONING HERE>

Original change's description:
> Remove memory used by unique glyphs
> 
> Change-Id: I789e9093e3fea9648b77a1bfda9d7b4b03b7f19d
> Reviewed-on: https://skia-review.googlesource.com/c/165025
> Reviewed-by: Mike Klein <mtklein@google.com>
> Commit-Queue: Herb Derby <herb@google.com>

TBR=mtklein@google.com,herb@google.com

Change-Id: If6d658fa348e55a4f1995ef0bd9025da6bb4d3cf
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://skia-review.googlesource.com/c/165311
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
3 files changed