Fix include directories in Windows GN build.

Fix include directories in Windows GN build.

Committed: https://crrev.com/22779180d946d0e4d90a7ee3e6345992f2c0422b
Cr-Commit-Position: refs/heads/master@{#311296}

[Slava Chigrin, 2015-01-13 15:23:45]

vchigrin@yandex-team.ru changed reviewers:
+ cjhopman@chromium.org, scottmg@chromium.org

[Slava Chigrin, 2015-01-13 15:46:05]

https://codereview.chromium.org/845363002/diff/1/build/json_schema_api.gni
File build/json_schema_api.gni (left):

https://codereview.chromium.org/845363002/diff/1/build/json_schema_api.gni#ol...
build/json_schema_api.gni:74: include_dirs = [ target_gen_dir ]
Here target_gen_dir is something like //out/gnRel/gen/extensions/common/api
and  root_gen_dir is like
//out/gnRel/gen

We must NOT add target_gen_dir  to the include path, since there is file
windows.h in directory //out/gnRel/gen/extensions/common/api . That causes
conflicts with system header with the same name, producing a lot of weird
compile errors on Windows.

Generated file included in chrome by more specific path, like
#include "chrome/common/extensions/api/windows.h" , so everyting should be OK
after that fix.

https://codereview.chromium.org/845363002/diff/1/build/secondary/third_party/...
File build/secondary/third_party/leveldatabase/BUILD.gn (left):

https://codereview.chromium.org/845363002/diff/1/build/secondary/third_party/...
build/secondary/third_party/leveldatabase/BUILD.gn:18: include_dirs += [
"src/port/win" ]
See https://codereview.chromium.org/27089002/ . Due to that wrong include
directory some other parts of the system pick stdint.h from leveldatabase,
instead of system one. That caused many compilation errors on Windows.

[scottmg, 2015-01-13 17:36:59]

lgtm

[Slava Chigrin, 2015-01-13 17:41:23]

The CQ bit was checked by vchigrin@yandex-team.ru

[commit-bot: I haz the power, 2015-01-13 17:41:51]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/845363002/1

[commit-bot: I haz the power, 2015-01-13 18:35:18]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-01-13 18:36:12]

Patchset 1 (id:??) landed as
https://crrev.com/22779180d946d0e4d90a7ee3e6345992f2c0422b
Cr-Commit-Position: refs/heads/master@{#311296}