Revert of Fix Blink commit type for subframes after initial about:blank load.

Revert of Fix Blink commit type for subframes after initial about:blank load. (patchset #5 id:100001 of https://codereview.chromium.org/1173513002/)

Reason for revert:
Broke SitePerProcessBrowserTest.NavigateRemoteFrame and SitePerProcessBrowserTest.NavigateRemoteFrameToBlankAndDataURLs.

Original issue's description:
> Fix Blink commit type for subframes after initial about:blank load.
> 
> This ensures that we do not create a new history item for whatever
> page replaces the initial about:blank page in an iframe.
> 
> BUG=464014, 310347, 178380
> TEST=Click a link in an initially about:blank iframe. No history item created.
> 
> Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=196964

TBR=japhet@chromium.org,creis@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=464014, 310347, 178380
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=196970

[dglazkov, 2015-06-11 20:18:42]

Created Revert of Fix Blink commit type for subframes after initial about:blank
load.

[commit-bot: I haz the power, 2015-06-11 20:18:55]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1177313002/1

[commit-bot: I haz the power, 2015-06-11 20:19:28]

Committed patchset #1 (id:1) as
https://src.chromium.org/viewvc/blink?view=rev&revision=196970

[Charlie Reis, 2015-06-12 03:48:25]

A revert of this CL (patchset #1 id:1) has been created in
https://codereview.chromium.org/1181973002/ by creis@chromium.org.

The reason for reverting is: Tests that failed after the original CL were
incorrect and have been disabled in https://codereview.chromium.org/1180013002/,
clearing the way for it to land again.  I'll watch the tree..