Revert of Refactoring: de-couple Extensions from "script injection System" [render side]:2

Revert of Refactoring: de-couple Extensions from "script injection System" [render side]:2 (patchset #8 id:350001 of https://codereview.chromium.org/906493004/)

Reason for revert:
broke the extension tests:

http://build.chromium.org/p/chromium.linux/builders/Linux%20Tests%20%28dbg%29%281%29%2832%29/builds/10543

Original issue's description:
> This CL adds routing info for content scripts from <webview>.
>
> To support dynamically added/removed content scripts in <webview>, we store
> these content scripts in the same shared memory where user scripts from
> declarative content API are stored, but the decision for injection will
> be made in the render once the url pattern is matched. Since render doesn't
> need to send IPCs to ask a decision from browser, it makes a precise time
> injection possible.
>
> Special to <webview>, once the content scripts are updated (added/removed),
> browser will only notify the render process of the given <webview>, rather than
> all of the renders (which is the case for user scripts).
>
> BUG=437566
>
> Committed: https://crrev.com/f853287c95cf818d0b5b02d7f4a6588761096d1c
> Cr-Commit-Position: refs/heads/master@{#318774}

TBR=rdevlin.cronin@chromium.org,fsamuel@chromium.org,hanxi@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=437566
Committed: https://crrev.com/9244b35bbc6b0907e70ca0e62d7ac063d7ef86e9
Cr-Commit-Position: refs/heads/master@{#318810}

[cpu_(ooo_6.6-7.5), 2015-03-03 00:48:29]

Created Revert of Refactoring: de-couple Extensions from "script injection
System" [render side]:2

[commit-bot: I haz the power, 2015-03-03 00:49:43]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/972863002/1

[commit-bot: I haz the power, 2015-03-03 00:50:49]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-03-03 00:51:40]

Patchset 1 (id:??) landed as
https://crrev.com/9244b35bbc6b0907e70ca0e62d7ac063d7ef86e9
Cr-Commit-Position: refs/heads/master@{#318810}