[ios] Fixed Resetting the page for unit tests.

[ios] Fixed Resetting the page for unit tests.

If |inner_html| is nil then comparing location with NSNotFound will
return YES. In Objective-C rangeOfString: must always compare length
with 0 instead because calling methods on nil return 0.

This bug was not exposed before because JS execution API could never
return nil and rangeOfString: worked correctly on empty strings.

BUG=637819
Committed: https://crrev.com/c7232e643ef714095d145dd2587c89bb33968b85
Cr-Commit-Position: refs/heads/master@{#412535}

[Eugene But (OOO till 7-30), 2016-08-17 14:49:40]

eugenebut@chromium.org changed reviewers:
+ justincohen@chromium.org, rohitrao@chromium.org

[Eugene But (OOO till 7-30), 2016-08-17 14:49:41]

I apologies, I did not notice this footgun in the code I was changing :(

[justincohen, 2016-08-17 14:50:36]

The CQ bit was checked by justincohen@chromium.org

[justincohen, 2016-08-17 14:50:36]

lgtm

[commit-bot: I haz the power, 2016-08-17 14:50:55]

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, 2016-08-17 15:27:13]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2016-08-17 15:29:21]

Description was changed from

==========
[ios] Fixed Resetting the page for unit tests.

If |inner_html| is nil then comparing location with NSNotFound will
return YES. In Objective-C rangeOfString: must always compare length
with 0 instead because calling methods on nil return 0.

This bug was not exposed before because JS execution API could never
return nil and rangeOfString: worked correctly on empty strings.

BUG=637819
==========

to

==========
[ios] Fixed Resetting the page for unit tests.

If |inner_html| is nil then comparing location with NSNotFound will
return YES. In Objective-C rangeOfString: must always compare length
with 0 instead because calling methods on nil return 0.

This bug was not exposed before because JS execution API could never
return nil and rangeOfString: worked correctly on empty strings.

BUG=637819

Committed: https://crrev.com/c7232e643ef714095d145dd2587c89bb33968b85
Cr-Commit-Position: refs/heads/master@{#412535}
==========

[commit-bot: I haz the power, 2016-08-17 15:29:21]

Patchset 2 (id:??) landed as
https://crrev.com/c7232e643ef714095d145dd2587c89bb33968b85
Cr-Commit-Position: refs/heads/master@{#412535}