Release Oilpan heap singletons prior to LSan leak detection.

third_party/WebKit/Source/platform/heap/ThreadState.cpp

Index: third_party/WebKit/Source/platform/heap/ThreadState.cpp
diff --git a/third_party/WebKit/Source/platform/heap/ThreadState.cpp b/third_party/WebKit/Source/platform/heap/ThreadState.cpp
index 5dade81422fb90875c853471da1f73fa91d9e779..1d476723a36e1c3bc1dea8a0f526dae1cccfa823 100644
--- a/third_party/WebKit/Source/platform/heap/ThreadState.cpp
+++ b/third_party/WebKit/Source/platform/heap/ThreadState.cpp
@@ -104,6 +104,9 @@ ThreadState::ThreadState()
 #if defined(ADDRESS_SANITIZER)
     , m_asanFakeStack(__asan_get_current_fake_stack())
 #endif
+#if defined(LEAK_SANITIZER)
+    , m_disabledStaticPersistentsRegistration(0)
+#endif
 {
     ASSERT(checkThread());
     ASSERT(!**s_threadSpecific);
@@ -1317,6 +1320,36 @@ void ThreadState::removeInterruptor(BlinkGCInterruptor* interruptor)
     }
 }
 
+#if defined(LEAK_SANITIZER)
+void ThreadState::registerStaticPersistentNode(PersistentNode* node)
+{
+    if (m_disabledStaticPersistentsRegistration)
+        return;
+
+    ASSERT(!m_staticPersistents.contains(node));
+    m_staticPersistents.add(node);
+}
+
+void ThreadState::releaseStaticPersistentNodes()
+{
+    for (PersistentNode* node : m_staticPersistents)
+        persistentRegion()->freePersistentNode(node);

[haraken, 2015/12/07 14:46:10]

After calling this, all static Persistent handles become stale pointers (i.e.,
pointing to freed persistent nodes). This is intentional, right?

I think this would be okay because this happens only when we shut down a
renderer with LSan enabled. It won't cause any practical issue.

[sof, 2015/12/07 16:59:17]

Intentional to handle it that way; the sweeping phase will poison what the
persistent points to via m_raw, so any attempted uses will be caught.

+
+    m_staticPersistents.clear();
+}
+
+void ThreadState::enterStaticReferenceRegistrationDisabledScope()
+{
+    m_disabledStaticPersistentsRegistration++;
+}
+
+void ThreadState::leaveStaticReferenceRegistrationDisabledScope()
+{
+    ASSERT(m_disabledStaticPersistentsRegistration);
+    m_disabledStaticPersistentsRegistration--;
+}
+#endif
+
 ThreadState::AttachedThreadStateSet& ThreadState::attachedThreads()
 {
     DEFINE_STATIC_LOCAL(AttachedThreadStateSet, threads, ());