Revert "Remove unique glyph IDs from glyph runs"

This reverts commit 2d123ad73f85f821c49961c0205f20d53e810cc8.

Reason for revert: Android roll?

Original change's description:
> Remove unique glyph IDs from glyph runs
> 
> The unique calculation is to costly to do for SkTextBlobs every
> time because there may be a cache hit in the GrTextBlob cache.
> In the future I will move the unique ID calculation to the GrTextBlob
> creation.
> 
> Change-Id: I7e10e8f22a3bc729fab12b2cf7e9732441be7f31
> Reviewed-on: https://skia-review.googlesource.com/c/164623
> Reviewed-by: Mike Klein <mtklein@google.com>
> Commit-Queue: Herb Derby <herb@google.com>

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

Change-Id: I8424e12e1ad1abd9e40699aa34e1062f5c7bf94a
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://skia-review.googlesource.com/c/165060
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
8 files changed