Added a promotion queue unit test that test promotion queue memory corruption

src/heap.h

Index: src/heap.h
diff --git a/src/heap.h b/src/heap.h
index 754b5588e05f89b11c8fffc7d77df82d5d29872a..f113c3ad49917b8dadf8197f96200f2dc16a4ad7 100644
--- a/src/heap.h
+++ b/src/heap.h
@@ -425,6 +425,12 @@ class PromotionQueue {
     RelocateQueueHead();
   }
 
+  bool IsBelowPromotionQueue(Address address) {

[titzer, 2014/07/01 11:58:20]

Can you split the condition up into multiple branches and add some comments as
to what each case means? (for future adventurers)

[Hannes Payer (out of office), 2014/07/01 16:08:12]

Done.

+    return (GetHeadPage() != Page::FromAddress(address) ||
+           NewSpacePage::IsAtStart(reinterpret_cast<Address>(rear_)) ||
+           reinterpret_cast<intptr_t*>(address) <= rear_);
+  }
+
   bool is_empty() {
     return (front_ == rear_) &&
         (emergency_stack_ == NULL || emergency_stack_->length() == 0);