Revert of [1b] Implement FetchBlobDataConsumerHandle

Revert of [1b] Implement FetchBlobDataConsumerHandle (patchset #18 id:320001 of https://codereview.chromium.org/1176403006/)

Reason for revert:
May have broken IndexedDBBrowserTestWithGCExposed.BlobDidAck.

Original issue's description:
> Implement FetchBlobDataConsumerHandle
> 
> Unit tests will be added in https://codereview.chromium.org/1199043004/.
> 
> FetchInitiatorTypeNames.in is modified to use FetchInitiatorTypeNames::internal from modules/.
> 
> BUG=480746
> 
> Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=198220

TBR=haraken@chromium.org,mkwst@chromium.org,oilpan-reviews@chromium.org,yhirano@chromium.org,hiroshige@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=480746
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=198229

[dcheng, 2015-07-02 17:18:53]

Created Revert of [1b] Implement FetchBlobDataConsumerHandle

[commit-bot: I haz the power, 2015-07-02 17:19:04]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1207273003/1

[commit-bot: I haz the power, 2015-07-02 17:19:40]

Committed patchset #1 (id:1) as
https://src.chromium.org/viewvc/blink?view=rev&revision=198229

[dcheng, 2015-07-02 18:20:11]

On 2015/07/02 at 17:19:40, commit-bot wrote:
> Committed patchset #1 (id:1) as
https://src.chromium.org/viewvc/blink?view=rev&revision=198229

I'll be relanding this, since it was another patch that caused this (see
https://crbug.com/506467).

[dcheng, 2015-07-02 18:20:26]

A revert of this CL (patchset #1 id:1) has been created in
https://codereview.chromium.org/1226563002/ by dcheng@chromium.org.

The reason for reverting is: Relanding..