[WebView] Remove onFailure from VisualStateCallback.

[WebView] Remove onFailure from VisualStateCallback.

onFailure is only invoked when the render frame has
been destroyed, but it is not really useful to
distinguish onComplete from onFailure in that case.
This also addresses the feedback that we received
from API Council.

This is a resubmit of CL 943633003

BUG=459539, 457184
Committed: https://crrev.com/8d503c0ae4a52ef7c935f98ae97f9582efdb660e
Cr-Commit-Position: refs/heads/master@{#319068}

[Tobias Sargeant, 2015-03-02 18:20:25]

tobiasjs@chromium.org changed reviewers:
+ boliu@chromium.org, piman@chromium.org

[Tobias Sargeant, 2015-03-02 18:20:26]

This CL also handles the propagation of swap failure information as requested by
+piman in the review of the previous CL (which I have duplicated in order to
take ownership from +igsolla).

[boliu, 2015-03-02 18:43:59]

This is not what Antoine suggested in
https://codereview.chromium.org/943633003#msg13

Let me rephrase it, and we can chat offline if any of this is not clear.

Before this change, if FrameHostMsg_VisualStateResponse comes back from
renderer, we assume it's a success. Otherwise (ie if RenderFrameHostImpl is
shutdown first), it's a failure.

The problem we are trying to address here is: a SwapPromise can fail, but still
sends FrameHostMsg_VisualStateResponse, which is treated as a success.

If you read https://code.google.com/p/chromium/issues/detail?id=459539#c1, the
only way a swap promise can "fail" for the visual state callback is due to
renderer being shutdown.

Shutdown order is not deterministic, but we can assume that if renderer shuts
down (or crashes) first, then browser side will be shutdown soon after as well.
So if renderer simply do not send FrameHostMsg_VisualStateResponse when the
error code is COMMIT_FAILS, then everything just works out.

https://codereview.chromium.org/974483002/diff/1/content/common/frame_messages.h
File content/common/frame_messages.h (right):

https://codereview.chromium.org/974483002/diff/1/content/common/frame_message...
content/common/frame_messages.h:846: // transport swap success/failure status.
Err, this is not it.

[Tobias Sargeant, 2015-03-03 12:39:12]

Reverted IPC-based implementation and replaced with simpler solution from
https://codereview.chromium.org/943633003#msg13. Needs testing.

[boliu, 2015-03-03 15:06:51]

lgtm

https://codereview.chromium.org/974483002/diff/40001/content/public/browser/r...
File content/public/browser/render_frame_host.h (left):

https://codereview.chromium.org/974483002/diff/40001/content/public/browser/r...
content/public/browser/render_frame_host.h:100: // the supplied |callback| with
a value of true upon successful completion and
should keep this comment

[Tobias Sargeant, 2015-03-03 15:15:51]

https://codereview.chromium.org/974483002/diff/40001/content/public/browser/r...
File content/public/browser/render_frame_host.h (left):

https://codereview.chromium.org/974483002/diff/40001/content/public/browser/r...
content/public/browser/render_frame_host.h:100: // the supplied |callback| with
a value of true upon successful completion and
On 2015/03/03 15:06:51, boliu wrote:
> should keep this comment

reinstated.

[piman, 2015-03-04 00:40:37]

LGTM, thanks

[Tobias Sargeant, 2015-03-04 10:29:50]

The CQ bit was checked by tobiasjs@chromium.org

[Tobias Sargeant, 2015-03-04 10:29:51]

The patchset sent to the CQ was uploaded after l-g-t-m from boliu@chromium.org
Link to the patchset: https://codereview.chromium.org/974483002/#ps60001 (title:
" ")

[commit-bot: I haz the power, 2015-03-04 10:30:48]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/974483002/60001

[Tobias Sargeant, 2015-03-04 13:41:46]

The CQ bit was checked by tobiasjs@chromium.org

[Tobias Sargeant, 2015-03-04 13:41:47]

The patchset sent to the CQ was uploaded after l-g-t-m from boliu@chromium.org,
piman@chromium.org
Link to the patchset: https://codereview.chromium.org/974483002/#ps80001 (title:
"Test fix")

[commit-bot: I haz the power, 2015-03-04 13:42:09]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/974483002/80001

[commit-bot: I haz the power, 2015-03-04 14:41:30]

Committed patchset #5 (id:80001)

[commit-bot: I haz the power, 2015-03-04 14:42:33]

Patchset 5 (id:??) landed as
https://crrev.com/8d503c0ae4a52ef7c935f98ae97f9582efdb660e
Cr-Commit-Position: refs/heads/master@{#319068}