Allow assertions to be enabled in Blink Release builds.

Source/platform/heap/Visitor.h

Index: Source/platform/heap/Visitor.h
diff --git a/Source/platform/heap/Visitor.h b/Source/platform/heap/Visitor.h
index ffadc80fe99aa42561c757d29f9432d498d39a52..b405d08c8ca4824d51c6826ae10d9621f7b3d882 100644
--- a/Source/platform/heap/Visitor.h
+++ b/Source/platform/heap/Visitor.h
@@ -51,7 +51,7 @@
 #include "wtf/text/WTFString.h"
 #endif
 
-#ifndef NDEBUG
+#if ENABLE(ASSERT)
 #define DEBUG_ONLY(x) x
 #else
 #define DEBUG_ONLY(x)
@@ -177,7 +177,7 @@ public:
         DefaultTraceTrait<T>::mark(visitor, t);
     }
 
-#ifndef NDEBUG
+#if ENABLE(ASSERT)
     static void checkGCInfo(Visitor* visitor, const T* t)
     {
         DefaultTraceTrait<T>::checkGCInfo(visitor, t);
@@ -217,7 +217,7 @@ public:
     {
         if (!t)
             return;
-#ifndef NDEBUG
+#if ENABLE(ASSERT)
         TraceTrait<T>::checkGCInfo(this, t);
 #endif
         TraceTrait<T>::mark(this, t);
@@ -392,7 +392,7 @@ public:
     }
 
     virtual void registerWeakTable(const void*, EphemeronCallback, EphemeronCallback) = 0;
-#ifndef NDEBUG
+#if ENABLE(ASSERT)
     virtual bool weakTableRegistered(const void*) = 0;
 #endif
 
@@ -413,7 +413,7 @@ public:
         return isAlive(ptr.get());
     }
 
-#ifndef NDEBUG
+#if ENABLE(ASSERT)
     void checkGCInfo(const void*, const GCInfo*);
 #endif
 
@@ -581,7 +581,7 @@ public:
         visitor->mark(const_cast<T*>(t), &TraceTrait<T>::trace);
     }
 
-#ifndef NDEBUG
+#if ENABLE(ASSERT)
     static void checkGCInfo(Visitor* visitor, const T* t)
     {
         visitor->checkGCInfo(const_cast<T*>(t), GCInfoTrait<T>::get());
@@ -598,7 +598,7 @@ public:
             self->adjustAndMark(visitor);
     }
 
-#ifndef NDEBUG
+#if ENABLE(ASSERT)
     static void checkGCInfo(Visitor*, const T*) { }
 #endif
 };