[heap] Use size_t for heap and space counters.

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"
@@ skipping 581 matching lines @@
 LargePage* LargePage::Initialize(Heap* heap, MemoryChunk* chunk,
                                  Executability executable, Space* owner) {
   if (executable && chunk->size() > LargePage::kMaxCodePageSize) {
     STATIC_ASSERT(LargePage::kMaxCodePageSize <= TypedSlotSet::kMaxOffset);
     FATAL("Code page is too large.");
   }
   heap->incremental_marking()->SetOldSpacePageFlags(chunk);
   return static_cast<LargePage*>(chunk);
 }
 
-
-intptr_t LargeObjectSpace::Available() {
+size_t LargeObjectSpace::Available() {
   return ObjectSizeFor(heap()->memory_allocator()->Available());
 }
 
 
 LocalAllocationBuffer LocalAllocationBuffer::InvalidBuffer() {
   return LocalAllocationBuffer(nullptr, AllocationInfo(nullptr, nullptr));
 }
 
 
 LocalAllocationBuffer LocalAllocationBuffer::FromResult(Heap* heap,
@@ skipping 15 matching lines @@
     other->allocation_info_.Reset(nullptr, nullptr);
     return true;
   }
   return false;
 }
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_HEAP_SPACES_INL_H_