Revert of Switch Chrome Android using v8 arch specific external data name

Revert of Switch Chrome Android using v8 arch specific external data name (patchset #5 id:80001 of https://codereview.chromium.org/1400953002/ )

Reason for revert:
Looks to have broken various Android Mojo tests:

http://build.chromium.org/p/chromium.linux/buildstatus?builder=Android%20GN&number=31621
http://build.chromium.org/p/chromium.linux/buildstatus?builder=Android%20GN&number=31622

Original issue's description:
> Switch Chrome Android using v8 arch specific external data name
>
> For 32-bit, natives_blob_32.bin and snapshot_blob_32.bin are used.
> For 64-bit, natives_blob_64.bin and natives_blob_64.bin are used.
>
> This patch also removed the existing v8 startup data in
> destination directory by using copy_ex to remove directory
> first.
>
> BUG=540788
>
> Committed: https://crrev.com/979b03a19f63b1cbe02fa3df99707c3f93f7c9cf
> Cr-Commit-Position: refs/heads/master@{#355680}

TBR=jochen@chromium.org,dpranke@chromium.org,halliwell@chromium.org,jbudorick@chromium.org,mef@chromium.org,rmcilroy@chromium.org,dtrainor@chromium.org,cpu@chromium.org,jam@chromium.org,michaelbai@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=540788
Committed: https://crrev.com/c2574ed2dede52cbf0353a3aca99d96cf0794571
Cr-Commit-Position: refs/heads/master@{#355697}

[DaleCurtis, 2015-10-23 01:05:29]

Created Revert of Switch Chrome Android using v8 arch specific external data
name

[commit-bot: I haz the power, 2015-10-23 01:05:50]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1419673008/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1419673008/1

[commit-bot: I haz the power, 2015-10-23 01:07:10]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-10-23 01:08:11]

Patchset 1 (id:??) landed as
https://crrev.com/c2574ed2dede52cbf0353a3aca99d96cf0794571
Cr-Commit-Position: refs/heads/master@{#355697}