Merged r14732, r14746, r14757 into 3.18 branch.

src/stub-cache.cc

Index: src/stub-cache.cc
diff --git a/src/stub-cache.cc b/src/stub-cache.cc
index 63748779b11c59a75f08aa77eb778ecc3f367277..8831713fe3457214a8463d6e165fbaf93643debf 100644
--- a/src/stub-cache.cc
+++ b/src/stub-cache.cc
@@ -1049,10 +1049,12 @@ void StubCache::Clear() {
   Code* empty = isolate_->builtins()->builtin(Builtins::kIllegal);
   for (int i = 0; i < kPrimaryTableSize; i++) {
     primary_[i].key = heap()->empty_string();
+    primary_[i].map = NULL;
     primary_[i].value = empty;
   }
   for (int j = 0; j < kSecondaryTableSize; j++) {
     secondary_[j].key = heap()->empty_string();
+    secondary_[j].map = NULL;
     secondary_[j].value = empty;
   }
 }