TBR: i#2121 date conversion: fix Windows build breakage

Commit log for first patchset:
---------------
i#2121 date conversion: fix Windows build breakage

Fixes Windows build breakage from f708ccc.
---------------

[bruening, 2017-01-23 16:35:38]

Committed as
https://github.com/DynamoRIO/dynamorio/commit/408e012beb50dac567612ef117f6149...

Final commit log: 
---------------
i#2121 date conversion: fix Windows build breakage

Fixes Windows build breakage from f708ccc.

Review-URL: https://codereview.appspot.com/315460043
---------------

[Edmund.Grimley.Evans, 2017-01-23 17:01:28]

LGTM, except that one of those casts is required to prevent overflow. It's kind
of my fault, really, for suggesting the casts might not be necessary, so I'll
push a fix in a moment.

[bruening, 2017-01-23 17:06:48]

Please hold off until AppVeyor is set up -- then you can use a pull request
to ensure it builds on Windows.  We are moving toward pull requests for
reviews with github's new rebase support, at least for those unable to run
a local Windows suite, so we have build coverage on all platforms
pre-commit.

On Mon, Jan 23, 2017 at 12:01 PM, <Edmund.Grimley.Evans@gmail.com> wrote:

> LGTM, except that one of those casts is required to prevent overflow.
> It's kind of my fault, really, for suggesting the casts might not be
> necessary, so I'll push a fix in a moment.
>
> https://codereview.appspot.com/315460043/
>

[Edmund.Grimley.Evans, 2017-01-23 17:10:28]

On 2017/01/23 17:06:48, bruening wrote:
> Please hold off until AppVeyor is set up -- then you can use a pull request
> to ensure it builds on Windows.  We are moving toward pull requests for
> reviews with github's new rebase support, at least for those unable to run
> a local Windows suite, so we have build coverage on all platforms
> pre-commit.

OK. An opportunity to test the new system. I'll wait.

[bruening, 2017-01-23 20:26:32]

Initial setup is complete.  Preliminary mods to wiki complete.  Precise
workflow still in flux though.

On Mon, Jan 23, 2017 at 12:10 PM, <Edmund.Grimley.Evans@gmail.com> wrote:

> On 2017/01/23 17:06:48, bruening wrote:
>
>> Please hold off until AppVeyor is set up -- then you can use a pull
>>
> request
>
>> to ensure it builds on Windows.  We are moving toward pull requests
>>
> for
>
>> reviews with github's new rebase support, at least for those unable to
>>
> run
>
>> a local Windows suite, so we have build coverage on all platforms
>> pre-commit.
>>
>
> OK. An opportunity to test the new system. I'll wait.
>
> https://codereview.appspot.com/315460043/
>

[bruening, 2017-01-23 21:21:22]

In case it wasn't clear, go ahead w/ the pull request.

On Mon, Jan 23, 2017 at 3:26 PM, Derek Bruening <bruening@google.com> wrote:

> Initial setup is complete.  Preliminary mods to wiki complete.  Precise
> workflow still in flux though.
>
> On Mon, Jan 23, 2017 at 12:10 PM, <Edmund.Grimley.Evans@gmail.com> wrote:
>
>> On 2017/01/23 17:06:48, bruening wrote:
>>
>>> Please hold off until AppVeyor is set up -- then you can use a pull
>>>
>> request
>>
>>> to ensure it builds on Windows.  We are moving toward pull requests
>>>
>> for
>>
>>> reviews with github's new rebase support, at least for those unable to
>>>
>> run
>>
>>> a local Windows suite, so we have build coverage on all platforms
>>> pre-commit.
>>>
>>
>> OK. An opportunity to test the new system. I'll wait.
>>
>> https://codereview.appspot.com/315460043/
>>
>
>

[Edmund.Grimley.Evans, 2017-01-24 09:27:13]

On 2017/01/23 21:21:22, bruening wrote:
> In case it wasn't clear, go ahead w/ the pull request.

Done, I think. What next?