Gate disabling nacl code on proper gyp flags, etc.

Background: I am currently trying to test NaCl in clank by setting disable_nacl=0 and enable_plugins=1 in gyp.  Some of the code required to get this to work is guarded under overly-specific OS==android and similar constructs.  This first CL enables a coherent build with the flags set to gyp, but does not yet turn the functionality on completely.  A sampling of issues fixed:

1) std:: prefix is more strictly observed on android
2) define NACL_LINUX, etc., is needed for nacl code
3) properly guard flag-setting code

BUG= https://code.google.com/p/nativeclient/issues/detail?id=3032
R=bradnelson@google.com, darin@chromium.org

Review URL: https://codereview.chromium.org/299703016

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@274839 0039d316-1c4b-4281-b951-d872f2087c98


CrOS-Libchrome-Original-Commit: d33d2224a994adfba4a55eb8d47706bbc67ff418
diff --git a/base/base.gypi b/base/base.gypi
index d0b7370..8144354 100644
--- a/base/base.gypi
+++ b/base/base.gypi
@@ -772,7 +772,7 @@
               ['include', '^threading/platform_thread_linux\\.cc$'],
             ],
           }],
-          ['OS == "android" and _toolset == "target"', {
+          ['OS == "android" and _toolset == "target" and >(nacl_untrusted_build)==0', {
            'sources': [
              'memory/discardable_memory_ashmem_allocator.cc',
              'memory/discardable_memory_ashmem_allocator.h',