[ios] Set WebState::IsLoading flag to false if load is cancelled.

[ios] Set WebState::IsLoading flag to false if load is cancelled.

Before this change WebState::IsLoading was returning false which caused
Toolbar to think that page did not finish loading. In M52 and earlier
toolbar was relying to CRWWebController.loadPhase API to check the load
state so this bug is M53 regression.

Keeping WebState::IsLoading in sync with CRWWebController.loadPhase
fixes toobar bug and is generally a reasonable thing to do.

BUG=638277
Review-Url: https://codereview.chromium.org/2250563003
Cr-Commit-Position: refs/heads/master@{#412391}
(cherry picked from commit 16e4de4de55c5c946b8bdfa47bfee274afc930f2)

Committed: https://chromium.googlesource.com/chromium/src/+/aa1c693955107d0e4d43ed59ebabe974ee698665

[Eugene But (OOO till 7-30), 2016-08-18 21:04:50]

Description was changed from

==========
[ios] Set WebState::IsLoading flag to false if load is cancelled.

Before this change WebState::IsLoading was returning false which caused
Toolbar to think that page did not finish loading. In M52 and earlier
toolbar was relying to CRWWebController.loadPhase API to check the load
state so this bug is M53 regression.

Keeping WebState::IsLoading in sync with CRWWebController.loadPhase
fixes toobar bug and is generally a reasonable thing to do.

BUG=638277

Review-Url: https://codereview.chromium.org/2250563003
Cr-Commit-Position: refs/heads/master@{#412391}
(cherry picked from commit 16e4de4de55c5c946b8bdfa47bfee274afc930f2)
==========

to

==========
[ios] Set WebState::IsLoading flag to false if load is cancelled.

Before this change WebState::IsLoading was returning false which caused
Toolbar to think that page did not finish loading. In M52 and earlier
toolbar was relying to CRWWebController.loadPhase API to check the load
state so this bug is M53 regression.

Keeping WebState::IsLoading in sync with CRWWebController.loadPhase
fixes toobar bug and is generally a reasonable thing to do.

BUG=638277

Review-Url: https://codereview.chromium.org/2250563003
Cr-Commit-Position: refs/heads/master@{#412391}
(cherry picked from commit 16e4de4de55c5c946b8bdfa47bfee274afc930f2)

Committed:
https://chromium.googlesource.com/chromium/src/+/aa1c693955107d0e4d43ed59ebab...
==========

[Eugene But (OOO till 7-30), 2016-08-18 21:04:52]

Committed patchset #1 (id:1) manually as
aa1c693955107d0e4d43ed59ebabe974ee698665.