Revert of clang upload.sh: don't download Clang binaries from clang_upload bots.

Revert of clang upload.sh: don't download Clang binaries from clang_upload bots. (patchset #3 id:40001 of https://codereview.chromium.org/1757733004/ )

Reason for revert:
Not needed anymore. https://codereview.chromium.org/1776893002/ was a better approach.

Original issue's description:
> clang upload.sh: don't download Clang binaries from clang_upload bots.
>
> Clang Upload trybots are used to build the new Clang
> binaries. Right now, they fail, because they try to download
> the not-yet-built clang revision during runhooks.
>
> In this CL a check into update.py is added to skip the
> download if it's running from Clang Upload trybot. LLVM_FORCE_LOCAL_BUILD env var is used for that.
>
> BUG=578306
>
> Committed: https://crrev.com/9321234d5ec76fadeacefd38591b93420dc62b67
> Cr-Commit-Position: refs/heads/master@{#379989}

TBR=thakis@chromium.org,hans@chromium.org,krasin@google.com
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=578306
Committed: https://crrev.com/729a518e05c01b45067d28c9eebfb05ef76043ff
Cr-Commit-Position: refs/heads/master@{#380072}

[krasin1, 2016-03-09 05:06:49]

Created Revert of clang upload.sh: don't download Clang binaries from
clang_upload bots.

[commit-bot: I haz the power, 2016-03-09 05:06:58]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1777793003/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1777793003/1

[commit-bot: I haz the power, 2016-03-09 05:07:20]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-03-09 05:08:28]

Description was changed from

==========
Revert of clang upload.sh: don't download Clang binaries from clang_upload bots.
(patchset #3 id:40001 of https://codereview.chromium.org/1757733004/ )

Reason for revert:
Not needed anymore. https://codereview.chromium.org/1776893002/ was a better
approach.

Original issue's description:
> clang upload.sh: don't download Clang binaries from clang_upload bots.
> 
> Clang Upload trybots are used to build the new Clang
> binaries. Right now, they fail, because they try to download
> the not-yet-built clang revision during runhooks.
> 
> In this CL a check into update.py is added to skip the
> download if it's running from Clang Upload trybot. LLVM_FORCE_LOCAL_BUILD env
var is used for that.
> 
> BUG=578306
> 
> Committed: https://crrev.com/9321234d5ec76fadeacefd38591b93420dc62b67
> Cr-Commit-Position: refs/heads/master@{#379989}

TBR=thakis@chromium.org,hans@chromium.org,krasin@google.com
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=578306
==========

to

==========
Revert of clang upload.sh: don't download Clang binaries from clang_upload bots.
(patchset #3 id:40001 of https://codereview.chromium.org/1757733004/ )

Reason for revert:
Not needed anymore. https://codereview.chromium.org/1776893002/ was a better
approach.

Original issue's description:
> clang upload.sh: don't download Clang binaries from clang_upload bots.
>
> Clang Upload trybots are used to build the new Clang
> binaries. Right now, they fail, because they try to download
> the not-yet-built clang revision during runhooks.
>
> In this CL a check into update.py is added to skip the
> download if it's running from Clang Upload trybot. LLVM_FORCE_LOCAL_BUILD env
var is used for that.
>
> BUG=578306
>
> Committed: https://crrev.com/9321234d5ec76fadeacefd38591b93420dc62b67
> Cr-Commit-Position: refs/heads/master@{#379989}

TBR=thakis@chromium.org,hans@chromium.org,krasin@google.com
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=578306

Committed: https://crrev.com/729a518e05c01b45067d28c9eebfb05ef76043ff
Cr-Commit-Position: refs/heads/master@{#380072}
==========

[commit-bot: I haz the power, 2016-03-09 05:08:29]

Patchset 1 (id:??) landed as
https://crrev.com/729a518e05c01b45067d28c9eebfb05ef76043ff
Cr-Commit-Position: refs/heads/master@{#380072}