Reland of [Fetch API] Start reading blob only when the reader wants to read contents.

Reland of [Fetch API] Start reading blob only when the reader wants to read contents. (patchset #1 id:1 of https://codereview.chromium.org/2319093004/ )

Reason for revert:
With the revert in place, the Linux MSAN is still failing:

https://uberchromegw.corp.google.com/i/chromium.webkit/builders/WebKit%20Linux%20MSAN/builds/12113

This proofs this patch to be innocent.

Original issue's description:
> Revert of [Fetch API] Start reading blob only when the reader wants to read contents. (patchset #3 id:40001 of https://codereview.chromium.org/2303753003/ )
>
> Reason for revert:
> Speculative revert: this patch is a suspect to cause Linux MSAN failures:
>
> https://uberchromegw.corp.google.com/i/chromium.webkit/builders/WebKit%20Linux%20MSAN/builds/12091
>
> The other suspected patch, the only one related to canvas, was reverted and didn't help.
>
> Original issue's description:
> > [Fetch API] Start reading blob only when the reader wants to read contents.
> >
> > BUG=643174
> >
> > Committed: https://crrev.com/f1ca96c413912ff1768e4274b8b7ac78eb41de64
> > Cr-Commit-Position: refs/heads/master@{#416923}
>
> TBR=hiroshige@chromium.org,jkarlin@chromium.org,yhirano@chromium.org
> # Not skipping CQ checks because original CL landed more than 1 days ago.
> BUG=643174
>
> Committed: https://crrev.com/2cbd2420c74783570442264a3e9a1c76cc42152e
> Cr-Commit-Position: refs/heads/master@{#417338}

TBR=hiroshige@chromium.org,jkarlin@chromium.org,yhirano@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=643174
Committed: https://crrev.com/a043096ac664aecc87fc5eb207c2ca84e892422e
Cr-Commit-Position: refs/heads/master@{#417391}

[lushnikov, 2016-09-08 20:50:17]

The CQ bit was checked by lushnikov@chromium.org

[lushnikov, 2016-09-08 20:50:18]

Created Reland of [Fetch API] Start reading blob only when the reader wants to
read contents.

[commit-bot: I haz the power, 2016-09-08 20:50:42]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-09-08 20:51:36]

Description was changed from

==========
Reland of [Fetch API] Start reading blob only when the reader wants to read
contents. (patchset #1 id:1 of https://codereview.chromium.org/2319093004/ )

Reason for revert:
With the revert in place, the Linux MSAN is still failing:

https://uberchromegw.corp.google.com/i/chromium.webkit/builders/WebKit%20Linu...

This proofs this patch to be innocent.

Original issue's description:
> Revert of [Fetch API] Start reading blob only when the reader wants to read
contents. (patchset #3 id:40001 of https://codereview.chromium.org/2303753003/ )
> 
> Reason for revert:
> Speculative revert: this patch is a suspect to cause Linux MSAN failures:
> 
>
https://uberchromegw.corp.google.com/i/chromium.webkit/builders/WebKit%20Linu...
> 
> The other suspected patch, the only one related to canvas, was reverted and
didn't help.
> 
> Original issue's description:
> > [Fetch API] Start reading blob only when the reader wants to read contents.
> >
> > BUG=643174
> >
> > Committed: https://crrev.com/f1ca96c413912ff1768e4274b8b7ac78eb41de64
> > Cr-Commit-Position: refs/heads/master@{#416923}
> 
> TBR=hiroshige@chromium.org,jkarlin@chromium.org,yhirano@chromium.org
> # Not skipping CQ checks because original CL landed more than 1 days ago.
> BUG=643174
> 
> Committed: https://crrev.com/2cbd2420c74783570442264a3e9a1c76cc42152e
> Cr-Commit-Position: refs/heads/master@{#417338}

TBR=hiroshige@chromium.org,jkarlin@chromium.org,yhirano@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=643174
==========

to

==========
Reland of [Fetch API] Start reading blob only when the reader wants to read
contents. (patchset #1 id:1 of https://codereview.chromium.org/2319093004/ )

Reason for revert:
With the revert in place, the Linux MSAN is still failing:

https://uberchromegw.corp.google.com/i/chromium.webkit/builders/WebKit%20Linu...

This proofs this patch to be innocent.

Original issue's description:
> Revert of [Fetch API] Start reading blob only when the reader wants to read
contents. (patchset #3 id:40001 of https://codereview.chromium.org/2303753003/ )
> 
> Reason for revert:
> Speculative revert: this patch is a suspect to cause Linux MSAN failures:
> 
>
https://uberchromegw.corp.google.com/i/chromium.webkit/builders/WebKit%20Linu...
> 
> The other suspected patch, the only one related to canvas, was reverted and
didn't help.
> 
> Original issue's description:
> > [Fetch API] Start reading blob only when the reader wants to read contents.
> >
> > BUG=643174
> >
> > Committed: https://crrev.com/f1ca96c413912ff1768e4274b8b7ac78eb41de64
> > Cr-Commit-Position: refs/heads/master@{#416923}
> 
> TBR=hiroshige@chromium.org,jkarlin@chromium.org,yhirano@chromium.org
> # Not skipping CQ checks because original CL landed more than 1 days ago.
> BUG=643174
> 
> Committed: https://crrev.com/2cbd2420c74783570442264a3e9a1c76cc42152e
> Cr-Commit-Position: refs/heads/master@{#417338}

TBR=hiroshige@chromium.org,jkarlin@chromium.org,yhirano@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=643174
==========

[commit-bot: I haz the power, 2016-09-08 20:51:37]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-09-08 20:52:58]

Description was changed from

==========
Reland of [Fetch API] Start reading blob only when the reader wants to read
contents. (patchset #1 id:1 of https://codereview.chromium.org/2319093004/ )

Reason for revert:
With the revert in place, the Linux MSAN is still failing:

https://uberchromegw.corp.google.com/i/chromium.webkit/builders/WebKit%20Linu...

This proofs this patch to be innocent.

Original issue's description:
> Revert of [Fetch API] Start reading blob only when the reader wants to read
contents. (patchset #3 id:40001 of https://codereview.chromium.org/2303753003/ )
> 
> Reason for revert:
> Speculative revert: this patch is a suspect to cause Linux MSAN failures:
> 
>
https://uberchromegw.corp.google.com/i/chromium.webkit/builders/WebKit%20Linu...
> 
> The other suspected patch, the only one related to canvas, was reverted and
didn't help.
> 
> Original issue's description:
> > [Fetch API] Start reading blob only when the reader wants to read contents.
> >
> > BUG=643174
> >
> > Committed: https://crrev.com/f1ca96c413912ff1768e4274b8b7ac78eb41de64
> > Cr-Commit-Position: refs/heads/master@{#416923}
> 
> TBR=hiroshige@chromium.org,jkarlin@chromium.org,yhirano@chromium.org
> # Not skipping CQ checks because original CL landed more than 1 days ago.
> BUG=643174
> 
> Committed: https://crrev.com/2cbd2420c74783570442264a3e9a1c76cc42152e
> Cr-Commit-Position: refs/heads/master@{#417338}

TBR=hiroshige@chromium.org,jkarlin@chromium.org,yhirano@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=643174
==========

to

==========
Reland of [Fetch API] Start reading blob only when the reader wants to read
contents. (patchset #1 id:1 of https://codereview.chromium.org/2319093004/ )

Reason for revert:
With the revert in place, the Linux MSAN is still failing:

https://uberchromegw.corp.google.com/i/chromium.webkit/builders/WebKit%20Linu...

This proofs this patch to be innocent.

Original issue's description:
> Revert of [Fetch API] Start reading blob only when the reader wants to read
contents. (patchset #3 id:40001 of https://codereview.chromium.org/2303753003/ )
>
> Reason for revert:
> Speculative revert: this patch is a suspect to cause Linux MSAN failures:
>
>
https://uberchromegw.corp.google.com/i/chromium.webkit/builders/WebKit%20Linu...
>
> The other suspected patch, the only one related to canvas, was reverted and
didn't help.
>
> Original issue's description:
> > [Fetch API] Start reading blob only when the reader wants to read contents.
> >
> > BUG=643174
> >
> > Committed: https://crrev.com/f1ca96c413912ff1768e4274b8b7ac78eb41de64
> > Cr-Commit-Position: refs/heads/master@{#416923}
>
> TBR=hiroshige@chromium.org,jkarlin@chromium.org,yhirano@chromium.org
> # Not skipping CQ checks because original CL landed more than 1 days ago.
> BUG=643174
>
> Committed: https://crrev.com/2cbd2420c74783570442264a3e9a1c76cc42152e
> Cr-Commit-Position: refs/heads/master@{#417338}

TBR=hiroshige@chromium.org,jkarlin@chromium.org,yhirano@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=643174

Committed: https://crrev.com/a043096ac664aecc87fc5eb207c2ca84e892422e
Cr-Commit-Position: refs/heads/master@{#417391}
==========

[commit-bot: I haz the power, 2016-09-08 20:52:59]

Patchset 1 (id:??) landed as
https://crrev.com/a043096ac664aecc87fc5eb207c2ca84e892422e
Cr-Commit-Position: refs/heads/master@{#417391}