Only add stubdata.c once on Windows (when icu_use_data_file_flag is set)

Only add stubdata.c once on Windows (when icu_use_data_file_flag is set)

It defaults to 1 everywhere except android webview, but it looks like
the windows condition wasn't updated after the switch.

TBR=jshin@chromium.org
R=jam@chromium.org
BUG=404809
Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=291179

[scottmg, 2014-08-19 04:02:30]

https://codereview.chromium.org/486103002/diff/1/icu.gyp
File icu.gyp (right):

https://codereview.chromium.org/486103002/diff/1/icu.gyp#newcode329
icu.gyp:329: [ 'OS == "win" and icu_use_data_file_flag==0', {
it's added in icudata at line 138 when icu_use_data_file_flag==1, so on windows,
it's added twice, which causes a link error when linking incrementally. i'm not
sure if it's important which target it's in?

[jam, 2014-08-21 20:48:48]

lgtm

[scottmg, 2014-08-21 20:49:26]

The CQ bit was checked by scottmg@chromium.org

[commit-bot: I haz the power, 2014-08-21 20:50:11]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/scottmg@chromium.org/486103002/1

[commit-bot: I haz the power, 2014-08-21 20:50:45]

Committed patchset #1 (1) as 291179