Issue #3562 - Use 'ToWstring()' to convert BSTR values

Issue #3562 - Use 'ToWstring()' to convert BSTR values

Use 'ToWstring()' to convert BSTR values from interfaces. This eliminates
all occurrences of 'SysStringLen()' in the plugin code. (One remains, of
course, in the implementation of 'ToWstring()').

A null BSTR pointer is the same as an empty string. Where needed, change the
logic around BSTR [out] arguments so that these two are treated identically.
This generally means converting first and testing 'empty()' afterwards.

[Eric, 2016-01-11 14:36:38]

This review also fixes some probably-inconsequential tiny defects dealing with
empty strings.

[sergei, 2016-01-11 15:39:07]

LGTM

https://codereview.adblockplus.org/29333350/diff/29333351/src/plugin/PluginCl...
File src/plugin/PluginClass.cpp (right):

https://codereview.adblockplus.org/29333350/diff/29333351/src/plugin/PluginCl...
src/plugin/PluginClass.cpp:180: DEBUG_ERROR_LOG(0, 0, 0,
"CPluginClass::GetBrowserUrl - Reached with m_webBrowser2 == nullptr");
The comment is slightly inconsistent now with the new logic.

[Eric, 2016-01-11 15:59:33]

Patch set 2 puts an error log message where it belongs.

https://codereview.adblockplus.org/29333350/diff/29333351/src/plugin/PluginCl...
File src/plugin/PluginClass.cpp (right):

https://codereview.adblockplus.org/29333350/diff/29333351/src/plugin/PluginCl...
src/plugin/PluginClass.cpp:180: DEBUG_ERROR_LOG(0, 0, 0,
"CPluginClass::GetBrowserUrl - Reached with m_webBrowser2 == nullptr");
On 2016/01/11 15:39:07, sergei wrote:
> The comment is slightly inconsistent now with the new logic.

Yeah. I'll fix that. That's an invariant violation we should be aware of.

[Oleksandr, 2016-01-22 12:40:01]

The changeset itself looks fine, however I think it involves too much subtle
changes for a Noissue commit. I would prefer to have either an issue created for
it (prefered), or push it with the codereview link. Otherwise it can be hard to
find the context.

[Oleksandr, 2016-01-22 12:43:44]

FYI I've created a ticket for this changeset:
https://issues.adblockplus.org/ticket/3562

[Eric, 2016-01-22 13:41:35]

No code changes. Changed issue description to reflect the change set message as
it will be committed.

[Oleksandr, 2016-01-22 14:06:24]

LGTM, thanks.

[sergei, 2016-01-22 14:35:38]

LGTM