Revert "Increase accuracy of float -> fixed in ICC code"

This reverts commit ef8dda227b55445de090cfc5c59fb633f8a1763d.

Reason for revert: This is breaking WebKit layout tests on linux and blocking the autoroller. Probably just needs a rebase. See:
https://storage.googleapis.com/chromium-layout-test-archives/linux_trusty_blink_rel/20229/layout-test-results/results.html

Original change's description:
> Increase accuracy of float -> fixed in ICC code
> 
> Add a comment to SkFixed explaining the accuracy issues of the macros.
> 
> Bug: skia:
> Change-Id: Ibfecb16821fefe87822cc3acd1cf8498df10a492
> Reviewed-on: https://skia-review.googlesource.com/85742
> Reviewed-by: Brian Osman <brianosman@google.com>
> Commit-Queue: Brian Osman <brianosman@google.com>

TBR=mtklein@chromium.org,brianosman@google.com,reed@google.com

Change-Id: I354327767bd59a6104b1431b053721c3102719be
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: skia:
Reviewed-on: https://skia-review.googlesource.com/86281
Reviewed-by: Eric Karl <ericrk@chromium.org>
Commit-Queue: Eric Karl <ericrk@chromium.org>
2 files changed