Revert "Add Thin LTO to OptimizeForSize builds"

This reverts commit 415a12a4a032684677d16985a8e1add8eafeb9ba.

Reason for revert: This makes codesize diffs impossible to read.

Original change's description:
> Add Thin LTO to OptimizeForSize builds
>
> Bug: skia:13657
> Change-Id: I289685ce71875fdc4d73f5e41107d87f5b5cdeb2
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/583248
> Commit-Queue: Brian Osman <brianosman@google.com>
> Reviewed-by: Ben Wagner <bungeman@google.com>

Bug: skia:13657
Change-Id: Ia67b6dd20a035b82da42e3cfd52118c0df4330ff
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/597156
Auto-Submit: Brian Osman <brianosman@google.com>
Commit-Queue: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
2 files changed