Revert of DevTools: Made id unique across different remote browsers

Revert of DevTools: Made id unique across different remote browsers (patchset #2 id:20001 of https://codereview.chromium.org/560523004/)

Reason for revert:
Need to delete the contents of chrome_beta_pages; see memory leak at https://build.chromium.org/p/chromium.memory/builders/Linux%20ASan%20LSan%20Tests%20(3)/builds/7887

Original issue's description:
> DevTools: Made id unique across different remote browsers
>
> BUG=338303
>
> Committed: https://crrev.com/7732fd3f76fc31a95f14199f898804e5d80e96e3
> Cr-Commit-Position: refs/heads/master@{#296188}

TBR=dgozman@chromium.org,pfeldman@chromium.org,vkuzkokov@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=338303
Committed: https://crrev.com/156c0428293ffd31af87b815ca72c3602afd75df
Cr-Commit-Position: refs/heads/master@{#296235}

[dewittj, 2014-09-23 17:18:55]

Created Revert of DevTools: Made id unique across different remote browsers

[commit-bot: I haz the power, 2014-09-23 17:59:19]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/598663002/1

[commit-bot: I haz the power, 2014-09-23 21:02:24]

Committed patchset #1 (id:1) as f1ea2cd8feff73656434821f6e6445aa30ca6847

[commit-bot: I haz the power, 2014-09-23 21:03:00]

Patchset 1 (id:??) landed as
https://crrev.com/156c0428293ffd31af87b815ca72c3602afd75df
Cr-Commit-Position: refs/heads/master@{#296235}