Enable ASan default options on Mac.

Enable ASan default options on Mac.

This CL links libsanitizer_options into every executable built with ASan on OSX.
The existing implementation of __asan_default_options for Chromium.app is merged with that in sanitizer_options.cc

Also now use_sanitizer_options is only set when building with sanitizers so that there isn't an unconditional dependency on an empty object file in every executable in non-sanitizer builds.

BUG=302040
R=cpu@chromium.org

Committed: https://crrev.com/0640a5d19ef72aec62787423e8a7c78c4f62b955
Cr-Commit-Position: refs/heads/master@{#295958}

[Alexander Potapenko, 2014-09-18 13:09:11]

glider@chromium.org changed reviewers:
+ cpu@chromium.org

[Alexander Potapenko, 2014-09-18 13:11:47]

Carlos, may I ask you to take a look?

[Alexander Potapenko, 2014-09-18 13:12:46]

glider@chromium.org changed reviewers:
+ earthdok@chromium.org

[Alexander Potapenko, 2014-09-18 13:12:47]

+Sergey for another pair of eyes on GYP

[earthdok, 2014-09-19 12:51:06]

lgtm

[cpu_(ooo_6.6-7.5), 2014-09-19 18:21:40]

rubber-stamp lgtm

[Alexander Potapenko, 2014-09-22 12:21:08]

The CQ bit was checked by glider@chromium.org

[commit-bot: I haz the power, 2014-09-22 12:22:07]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/581983003/60001

[commit-bot: I haz the power, 2014-09-22 13:20:22]

Committed patchset #4 (id:60001) as bde5f70d022b914fcae2d0687a94ef9672c93993

[commit-bot: I haz the power, 2014-09-22 13:20:59]

Patchset 4 (id:??) landed as
https://crrev.com/0640a5d19ef72aec62787423e8a7c78c4f62b955
Cr-Commit-Position: refs/heads/master@{#295958}

[Alexander Potapenko, 2014-09-22 16:31:45]

A revert of this CL (patchset #4 id:60001) has been created in
https://codereview.chromium.org/593683004/ by glider@chromium.org.

The reason for reverting is: This CL broke ui_unittests on both Mac ASan and Mac
ASan 64 bots:

/Volumes/data/bool/build/slave/Mac_ASan_Tests__2_/build/src/out/Release/ui_unittests
--brave-new-test-launcher --test-launcher-bot-mode --verbose
--test-launcher-print-test-stdio=always --gtest_print_time
--test-launcher-summary-output=/tmp/tmpnPVxX8
dyld: Library not loaded: @executable_path/../Versions/1.0.0.0/ui_unittests
Framework.framework/ui_unittests Framework
  Referenced from:
/Volumes/data/bool/build/slave/Mac_ASan_Tests__2_/build/src/out/Release/ui_unittests
  Reason: image not found

http://build.chromium.org/p/chromium.memory/builders/Mac%20ASan%20Tests%20%28....