Revert of Disable support for swapped out RenderFrame(Host) on desktop.

Revert of Disable support for swapped out RenderFrame(Host) on desktop. (patchset #16 id:300001 of https://codereview.chromium.org/1199313006/ )

Reason for revert:
This CL is the culprit of RenderFrameHostManagerTest.NoScriptAccessAfterSwapOut content_browsertests failure on TSan bots

BUG=537689
Original issue's description:
> Disable support for swapped out RenderFrame(Host) on desktop.
>
> This CL disables the usage of swapped out RenderFrame(Host) objects. Instead
> RenderFrameProxy(Host) is used. Disabling is done through setting a
> boolean value in checking for swapped out support and the actual code
> will be removed in follow up CLs, once this one sticks and no issues are found.
>
> Android is left alone, as troubleshooting why content_browsertests is failing
> on the bots is very time consuming. Follow up patch will disable it there too.
>
> BUG=357747
>
> Committed: https://crrev.com/b8cc9ba3b9d0b8478bfd5d63130dfcfc69fbe6e6
> Cr-Commit-Position: refs/heads/master@{#351446}

TBR=creis@chromium.org,nasko@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=357747
Committed: https://crrev.com/e8a98e91d731af4c74f7e933727517fa2b924f87
Cr-Commit-Position: refs/heads/master@{#351597}

[zhaoqin1, 2015-09-30 18:09:22]

Created Revert of Disable support for swapped out RenderFrame(Host) on desktop.

[commit-bot: I haz the power, 2015-09-30 18:11:52]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1374543004/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1374543004/1

[commit-bot: I haz the power, 2015-09-30 18:13:58]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-09-30 18:14:53]

Patchset 1 (id:??) landed as
https://crrev.com/e8a98e91d731af4c74f7e933727517fa2b924f87
Cr-Commit-Position: refs/heads/master@{#351597}