gn win: Fix potentially uninitialized variable warning in zip_internal

gn win: Fix potentially uninitialized variable warning in zip_internal

The gn Windows build says

d:\src\cr3\src\third_party\zlib\google\zip_internal.cc(62) : error C2220: warning treated as error - no 'object' file generated
d:\src\cr3\src\third_party\zlib\google\zip_internal.cc(62) : warning C4701: potentially uninitialized local variable 'creation_disposition' used

This warning is disabled in the gyp build, but it seems better to keep
it on if possible, and it seems like depending on the flags passed to
ZipOpenFunc, it could indeed be passing an uninitialized value to
::CreateFile. Setting it explicitly to 0 will cause ::CreateFile to
fail, if it's left unset by the ifs.

R=satorux@chromium.org
BUG=354261
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=286711

[satorux1, 2014-07-30 21:40:40]

LGTM with an optional request:

https://codereview.chromium.org/430963002/diff/1/third_party/zlib/google/zip_...
File third_party/zlib/google/zip_internal.cc (right):

https://codereview.chromium.org/430963002/diff/1/third_party/zlib/google/zip_...
third_party/zlib/google/zip_internal.cc:41: DWORD share_mode,
flags_and_attributes;
while you are at it, could you change the code to initialize them with 0 here?

[scottmg, 2014-07-30 21:43:44]

Thanks

https://codereview.chromium.org/430963002/diff/1/third_party/zlib/google/zip_...
File third_party/zlib/google/zip_internal.cc (right):

https://codereview.chromium.org/430963002/diff/1/third_party/zlib/google/zip_...
third_party/zlib/google/zip_internal.cc:41: DWORD share_mode,
flags_and_attributes;
On 2014/07/30 21:40:39, satorux1 wrote:
> while you are at it, could you change the code to initialize them with 0 here?

Done.

[scottmg, 2014-07-30 21:44:13]

The CQ bit was checked by scottmg@chromium.org

[commit-bot: I haz the power, 2014-07-30 21:45:49]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/scottmg@chromium.org/430963002/20001

[commit-bot: I haz the power, 2014-07-31 03:35:02]

Change committed as 286711