Various ASan exemptions to allow Oilpan pre-sweep poisoning of unmarkeds.

Source/wtf/LinkedHashSet.h

Index: Source/wtf/LinkedHashSet.h
diff --git a/Source/wtf/LinkedHashSet.h b/Source/wtf/LinkedHashSet.h
index 541976db84283fe73038ed326cd5e0b79ab42d6b..d8342e2316c47f42703dd4613331bd80b11b66fe 100644
--- a/Source/wtf/LinkedHashSet.h
+++ b/Source/wtf/LinkedHashSet.h
@@ -27,6 +27,17 @@
 #include "wtf/OwnPtr.h"
 #include "wtf/PassOwnPtr.h"
 
+// TODO(sof): See NO_SANITIZE_ADDRESS comment in platform/heap/AddressSanitizer.h
+// on the Windows toolchain special case; that comment also covers why we
+// temporarily need this NO_LAZY_SWEEP_SANITIZE_ADDRESS_WTF annotation.
+// (macro repeatedly defined here so as to avoid introducing an improper
+// wtf/ => platform/ dependency.)
+#if defined(ADDRESS_SANITIZER) && ENABLE(OILPAN) && (!OS(WIN) || COMPILER(CLANG))
+#define NO_LAZY_SWEEP_SANITIZE_ADDRESS_WTF __attribute__((no_sanitize_address))
+#else
+#define NO_LAZY_SWEEP_SANITIZE_ADDRESS_WTF
+#endif
+
 namespace WTF {
 
 // LinkedHashSet: Just like HashSet, this class provides a Set
@@ -53,6 +64,7 @@ class LinkedHashSetNodeBase {
 public:
     LinkedHashSetNodeBase() : m_prev(this), m_next(this) { }
 
+    NO_LAZY_SWEEP_SANITIZE_ADDRESS_WTF
     void unlink()
     {
         if (!m_next)