Partition libcxx build code from build/config/sanitizers

build/sanitizers/sanitizer_options.cc

Index: build/sanitizers/sanitizer_options.cc
diff --git a/build/sanitizers/sanitizer_options.cc b/build/sanitizers/sanitizer_options.cc
index 1f4250111ec89262343113b6bd55cb59b2580f0a..e7e427981f9e41acd877c807163197cf998af966 100644
--- a/build/sanitizers/sanitizer_options.cc
+++ b/build/sanitizers/sanitizer_options.cc
@@ -82,24 +82,16 @@ const char *kAsanDefaultOptions =
     "check_printf=1 use_sigaltstack=1 "
     "strip_path_prefix=/../../ fast_unwind_on_fatal=1 "
     "detect_stack_use_after_return=1 detect_odr_violation=0 ";
-static const char kNaClDefaultOptions[] = "handle_segv=0";
-static const char kNaClFlag[] = "--type=nacl-loader";
 #endif  // OS_LINUX
 
 #if defined(OS_LINUX) || defined(OS_MACOSX)
+// Allow NaCl to override the default asan options.
+extern const char* kAsanDefaultOptionsNaCl;
+__attribute__((weak)) const char* kAsanDefaultOptionsNaCl = nullptr;
+
 SANITIZER_HOOK_ATTRIBUTE const char *__asan_default_options() {
-#if defined(OS_MACOSX)
-  char*** argvp = _NSGetArgv();
-  int* argcp = _NSGetArgc();
-  if (!argvp || !argcp) return kAsanDefaultOptions;
-  char** argv = *argvp;
-  int argc = *argcp;
-  for (int i = 0; i < argc; ++i) {
-    if (strcmp(argv[i], kNaClFlag) == 0) {
-      return kNaClDefaultOptions;
-    }
-  }
-#endif
+  if (kAsanDefaultOptionsNaCl)
+    return kAsanDefaultOptionsNaCl;
   return kAsanDefaultOptions;
 }