Revert of Fix RGBA alpha parsing and serialization to adhere to W3 standard.

Revert of Fix RGBA alpha parsing and serialization to adhere to W3 standard. (patchset #15 id:280001 of https://codereview.chromium.org/2608423002/ )

Reason for revert:
This CL causes Mac Retina to fail webkit tests fast/forms/select/menulist-appearance-basic.html
: https://build.chromium.org/p/chromium.webkit/builders/WebKit%20Mac10.11%20%28retina%29/builds/10963

Original issue's description:
> Fix RGBA alpha parsing and serialization to adhere to W3 standard.
> 
> Specifically, a 2.55 multiplication factor should be used, and
> serialization should be to two or three digits according to section
> <alphavalue> in https://drafts.csswg.org/cssom/#serializing-css-values
> 
> This fixes test case "background-color: rgba(5, 7, 10, 0.5)" in
> https://w3c-test.org/cssom/serialize-values.html and also that the
> implementation is now same as Firefox as noted in the bug.
> 
> Note a large number of tests need to be fixed, many of them because:
> - *-expected.txt specifically had bad alpha values such as 0.501961 or
> - an alpha value of 0.5 was previously 127 but should have been 128.
> The latter applies to the updated expected images too where the only
> difference was tiny bit of alpha (and rgb when alpha blended) change.
> 
> BUG=453414
> 
> Review-Url: https://codereview.chromium.org/2608423002
> Cr-Commit-Position: refs/heads/master@{#443157}
> Committed: https://chromium.googlesource.com/chromium/src/+/13a86c2faeebcbc12dd4a7e8dea54318da635c19

TBR=sashab@chromium.org,eae@chromium.org,ktyliu@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=453414
Review-Url: https://codereview.chromium.org/2629163002
Cr-Commit-Position: refs/heads/master@{#443281}
Committed: https://chromium.googlesource.com/chromium/src/+/1edf45295cda206bcf8e8479d7cf94dd9b408b1d

[eae, 2017-01-12 17:32:29]

LGTM

[xlai (Olivia), 2017-01-12 17:40:29]

The CQ bit was checked by xlai@chromium.org

[xlai (Olivia), 2017-01-12 17:40:32]

The patchset sent to the CQ was uploaded after l-g-t-m from eae@chromium.org
Link to the patchset: https://codereview.chromium.org/2629163002/#ps340001
(title: "fix conflicts")

[commit-bot: I haz the power, 2017-01-12 17:41:07]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-01-12 17:49:29]

CQ is committing da patch.

Bot data: {"patchset_id": 340001, "attempt_start_ts": 1484242829695260,
"parent_rev": "5e234b7e88e8a8f0c48de5713460fe600d510e72", "commit_rev":
"1edf45295cda206bcf8e8479d7cf94dd9b408b1d"}

[commit-bot: I haz the power, 2017-01-12 17:50:32]

Description was changed from

==========
Revert of Fix RGBA alpha parsing and serialization to adhere to W3 standard.
(patchset #15 id:280001 of https://codereview.chromium.org/2608423002/ )

Reason for revert:
This CL causes Mac Retina to fail webkit tests
fast/forms/select/menulist-appearance-basic.html
:
https://build.chromium.org/p/chromium.webkit/builders/WebKit%20Mac10.11%20%28...

Original issue's description:
> Fix RGBA alpha parsing and serialization to adhere to W3 standard.
> 
> Specifically, a 2.55 multiplication factor should be used, and
> serialization should be to two or three digits according to section
> <alphavalue> in https://drafts.csswg.org/cssom/#serializing-css-values
> 
> This fixes test case "background-color: rgba(5, 7, 10, 0.5)" in
> https://w3c-test.org/cssom/serialize-values.html and also that the
> implementation is now same as Firefox as noted in the bug.
> 
> Note a large number of tests need to be fixed, many of them because:
> - *-expected.txt specifically had bad alpha values such as 0.501961 or
> - an alpha value of 0.5 was previously 127 but should have been 128.
> The latter applies to the updated expected images too where the only
> difference was tiny bit of alpha (and rgb when alpha blended) change.
> 
> BUG=453414
> 
> Review-Url: https://codereview.chromium.org/2608423002
> Cr-Commit-Position: refs/heads/master@{#443157}
> Committed:
https://chromium.googlesource.com/chromium/src/+/13a86c2faeebcbc12dd4a7e8dea5...

TBR=sashab@chromium.org,eae@chromium.org,ktyliu@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=453414
==========

to

==========
Revert of Fix RGBA alpha parsing and serialization to adhere to W3 standard.
(patchset #15 id:280001 of https://codereview.chromium.org/2608423002/ )

Reason for revert:
This CL causes Mac Retina to fail webkit tests
fast/forms/select/menulist-appearance-basic.html
:
https://build.chromium.org/p/chromium.webkit/builders/WebKit%20Mac10.11%20%28...

Original issue's description:
> Fix RGBA alpha parsing and serialization to adhere to W3 standard.
> 
> Specifically, a 2.55 multiplication factor should be used, and
> serialization should be to two or three digits according to section
> <alphavalue> in https://drafts.csswg.org/cssom/#serializing-css-values
> 
> This fixes test case "background-color: rgba(5, 7, 10, 0.5)" in
> https://w3c-test.org/cssom/serialize-values.html and also that the
> implementation is now same as Firefox as noted in the bug.
> 
> Note a large number of tests need to be fixed, many of them because:
> - *-expected.txt specifically had bad alpha values such as 0.501961 or
> - an alpha value of 0.5 was previously 127 but should have been 128.
> The latter applies to the updated expected images too where the only
> difference was tiny bit of alpha (and rgb when alpha blended) change.
> 
> BUG=453414
> 
> Review-Url: https://codereview.chromium.org/2608423002
> Cr-Commit-Position: refs/heads/master@{#443157}
> Committed:
https://chromium.googlesource.com/chromium/src/+/13a86c2faeebcbc12dd4a7e8dea5...

TBR=sashab@chromium.org,eae@chromium.org,ktyliu@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=453414

Review-Url: https://codereview.chromium.org/2629163002
Cr-Commit-Position: refs/heads/master@{#443281}
Committed:
https://chromium.googlesource.com/chromium/src/+/1edf45295cda206bcf8e8479d7cf...
==========

[commit-bot: I haz the power, 2017-01-12 17:50:34]

Committed patchset #4 (id:340001) as
https://chromium.googlesource.com/chromium/src/+/1edf45295cda206bcf8e8479d7cf...