Preliminary Harmony weak maps API implementation.

src/objects-debug.cc

Index: src/objects-debug.cc
diff --git a/src/objects-debug.cc b/src/objects-debug.cc
index 29632317a5e9309ee456c2e0ce9042b0b4c48cdf..0ab36c6f08d2d60afa385350656140aca9c0fe8f 100644
--- a/src/objects-debug.cc
+++ b/src/objects-debug.cc
@@ -153,6 +153,9 @@ void HeapObject::HeapObjectVerify() {
     case JS_ARRAY_TYPE:
       JSArray::cast(this)->JSArrayVerify();
       break;
+    case JS_WEAK_MAP_TYPE:
+      JSWeakMap::cast(this)->JSWeakMapVerify();
+      break;
     case JS_REGEXP_TYPE:
       JSRegExp::cast(this)->JSRegExpVerify();
       break;
@@ -453,6 +456,14 @@ void JSArray::JSArrayVerify() {
 }
 
 
+void JSWeakMap::JSWeakMapVerify() {
+  CHECK(IsJSWeakMap());
+  JSObjectVerify();
+  VerifyHeapPointer(table());
+  ASSERT(table()->IsHashTable());
+}
+
+
 void JSRegExp::JSRegExpVerify() {
   JSObjectVerify();
   ASSERT(data()->IsUndefined() || data()->IsFixedArray());