Revert of Flip 'Linux x64' bot on chromium waterfall to GN.

Revert of Flip 'Linux x64' bot on chromium waterfall to GN. (patchset #2 id:20001 of https://codereview.chromium.org/1461453002/ )

Reason for revert:
compiling 'all' fails w/ GN:

http://build.chromium.org/p/chromium/builders/Linux%20x64/builds/12149/steps/compile/logs/stdio

Original issue's description:
> Flip 'Linux x64' bot on chromium waterfall to GN.
>
> This flips the Linux x64 bot on the chromium waterfall to
> GN, and cleans up some mistakes in the MB config (the
> builders should've been setting linux_dump_symbols=0,
> which is the default, not linux_dump_symbols=1).
>
> TBR=phajdan.jr@chromium.org, brettw@chromium.org
> BUG=530733, 432959
>
> Committed: https://crrev.com/9bb757129af95f0ca1539c65269cd8bc85df04f8
> Cr-Commit-Position: refs/heads/master@{#360510}

TBR=phajdan.jr@chromium.org,brettw@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=530733, 432959
Committed: https://crrev.com/8712d995456e8ec14f36cdfbf16086175d9011ac
Cr-Commit-Position: refs/heads/master@{#360544}

[Dirk Pranke, 2015-11-19 08:48:41]

Created Revert of Flip 'Linux x64' bot on chromium waterfall to GN.

[commit-bot: I haz the power, 2015-11-19 08:49:15]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1457593005/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1457593005/1

[commit-bot: I haz the power, 2015-11-19 08:50:58]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-11-19 08:52:05]

Patchset 1 (id:??) landed as
https://crrev.com/8712d995456e8ec14f36cdfbf16086175d9011ac
Cr-Commit-Position: refs/heads/master@{#360544}