Ensure that executable pages are properly guarded.

src/heap-inl.h

Index: src/heap-inl.h
diff --git a/src/heap-inl.h b/src/heap-inl.h
index 39cdf139e83b9e5e0683037c412f671385156331..81ed448a17f1185b3bd64d7577f29a001db0a42b 100644
--- a/src/heap-inl.h
+++ b/src/heap-inl.h
@@ -49,7 +49,7 @@ void PromotionQueue::insert(HeapObject* target, int size) {
     NewSpacePage* rear_page =
         NewSpacePage::FromAddress(reinterpret_cast<Address>(rear_));
     ASSERT(!rear_page->prev_page()->is_anchor());
-    rear_ = reinterpret_cast<intptr_t*>(rear_page->prev_page()->body_limit());
+    rear_ = reinterpret_cast<intptr_t*>(rear_page->prev_page()->area_end());
     ActivateGuardIfOnTheSamePage();
   }
 
@@ -81,11 +81,6 @@ void PromotionQueue::ActivateGuardIfOnTheSamePage() {
 }
 
 
-int Heap::MaxObjectSizeInPagedSpace() {
-  return Page::kMaxHeapObjectSize;
-}
-
-
 MaybeObject* Heap::AllocateStringFromUtf8(Vector<const char> str,
                                           PretenureFlag pretenure) {
   // Check for ASCII first since this is the common case.
@@ -119,7 +114,7 @@ MaybeObject* Heap::AllocateAsciiSymbol(Vector<const char> str,
 
   // Allocate string.
   Object* result;
-  { MaybeObject* maybe_result = (size > MaxObjectSizeInPagedSpace())
+  { MaybeObject* maybe_result = (size > Page::kMaxNonCodeHeapObjectSize)
                    ? lo_space_->AllocateRaw(size, NOT_EXECUTABLE)
                    : old_data_space_->AllocateRaw(size);
     if (!maybe_result->ToObject(&result)) return maybe_result;
@@ -153,7 +148,7 @@ MaybeObject* Heap::AllocateTwoByteSymbol(Vector<const uc16> str,
 
   // Allocate string.
   Object* result;
-  { MaybeObject* maybe_result = (size > MaxObjectSizeInPagedSpace())
+  { MaybeObject* maybe_result = (size > Page::kMaxNonCodeHeapObjectSize)
                    ? lo_space_->AllocateRaw(size, NOT_EXECUTABLE)
                    : old_data_space_->AllocateRaw(size);
     if (!maybe_result->ToObject(&result)) return maybe_result;