[heap] Fix address space leak in Unmapper

src/heap/spaces-inl.h

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_HEAP_SPACES_INL_H_
 #define V8_HEAP_SPACES_INL_H_
 
 #include "src/heap/incremental-marking.h"
 #include "src/heap/spaces.h"
 #include "src/isolate.h"
 #include "src/msan.h"
 #include "src/profiler/heap-profiler.h"
 #include "src/v8memory.h"
 
 namespace v8 {
 namespace internal {
 
+template <MemoryAllocator::AllocationMode alloc_mode, typename SpaceType>
+Page* MemoryAllocator::AllocatePage(size_t size, SpaceType* owner,
+                                    Executability executable) {
+  MemoryChunk* chunk = nullptr;
+  if (alloc_mode == kPooled) {
+    DCHECK_EQ(size, static_cast<size_t>(MemoryChunk::kAllocatableMemory));
+    DCHECK_EQ(executable, NOT_EXECUTABLE);
+    chunk = AllocatePagePooled(owner);
+  }
+  if (chunk == nullptr) {
+    chunk = AllocateChunk(size, size, executable, owner);
+  }
+  if (chunk == nullptr) return nullptr;
+  return Page::Initialize(isolate_->heap(), chunk, executable, owner);
+}
+
 template <class PAGE_TYPE>
 PageIteratorImpl<PAGE_TYPE>& PageIteratorImpl<PAGE_TYPE>::operator++() {
   p_ = p_->next_page();
   return *this;
 }
 
 template <class PAGE_TYPE>
 PageIteratorImpl<PAGE_TYPE> PageIteratorImpl<PAGE_TYPE>::operator++(int) {
   PageIteratorImpl<PAGE_TYPE> tmp(*this);
   operator++();
@@ skipping 611 matching lines @@
     other->allocation_info_.Reset(nullptr, nullptr);
     return true;
   }
   return false;
 }
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_HEAP_SPACES_INL_H_