Revert r16648, r16641, r16638 and r16637.

src/spaces-inl.h

Index: src/spaces-inl.h
diff --git a/src/spaces-inl.h b/src/spaces-inl.h
index 37002e68801b2928558b3533adc72e484d29120f..be2ae2a57db248234ab9f92726beec0168a49709 100644
--- a/src/spaces-inl.h
+++ b/src/spaces-inl.h
@@ -125,11 +125,43 @@ HeapObject* HeapObjectIterator::FromCurrentPage() {
 }
 
 
+// -----------------------------------------------------------------------------
+// MemoryAllocator
+
+#ifdef ENABLE_HEAP_PROTECTION
+
+void MemoryAllocator::Protect(Address start, size_t size) {
+  OS::Protect(start, size);
+}
+
+
+void MemoryAllocator::Unprotect(Address start,
+                                size_t size,
+                                Executability executable) {
+  OS::Unprotect(start, size, executable);
+}
+
+
+void MemoryAllocator::ProtectChunkFromPage(Page* page) {
+  int id = GetChunkId(page);
+  OS::Protect(chunks_[id].address(), chunks_[id].size());
+}
+
+
+void MemoryAllocator::UnprotectChunkFromPage(Page* page) {
+  int id = GetChunkId(page);
+  OS::Unprotect(chunks_[id].address(), chunks_[id].size(),
+                chunks_[id].owner()->executable() == EXECUTABLE);
+}
+
+#endif
+
+
 // --------------------------------------------------------------------------
 // PagedSpace
 Page* Page::Initialize(Heap* heap,
                        MemoryChunk* chunk,
-                       VirtualMemory::Executability executability,
+                       Executability executable,
                        PagedSpace* owner) {
   Page* page = reinterpret_cast<Page*>(chunk);
   ASSERT(page->area_size() <= kNonCodeObjectAreaSize);