GitLab

This reverts commit 4d9450df.

Reason for revert: Likely caused the test PartitionAllocTest.DumpMemoryStats failing consistently in android x86 builders since:
* https://ci.chromium.org/p/chromium/builders/ci/android-marshmallow-x86-rel/1084
* https://ci.chromium.org/p/chromium/builders/ci/android-pie-x86-rel/1992

Original change's description:
> [PartitionAlloc] Use reciprocal multiplication to speed up GetSlotOffset
> 
> Currently, the "get offset of a pointer within its allocated slot"
> functionality, which is used extensively by several MiraclePtr
> implementations, performs an expensive modulo operation. This commit
> replaces it with a cheaper sequence of multiplications and bit shifts.
> 
> Bug: 1092288
> Change-Id: I866689a79fff704b5f83fc07d8f28b3386ef644d
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2335443
> Commit-Queue: Sergei Glazunov <glazunov@google.com>
> Reviewed-by: Benoit L <lizeb@chromium.org>
> Reviewed-by: Bartek Nowierski <bartekn@chromium.org>
> Reviewed-by: Kentaro Hara <haraken@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#802194}

TBR=haraken@chromium.org,lizeb@chromium.org,bartekn@chromium.org,glazunov@google.com

Change-Id: Iaed8d78231201dd69a880e8a30028ddd64bead94
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 1092288
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2380107Reviewed-by: Haiyang Pan <hypan@google.com>
Commit-Queue: Haiyang Pan <hypan@google.com>
Cr-Commit-Position: refs/heads/master@{#802323}