Fix invalid use of int in Zone.

src/lithium-allocator.cc

 // Copyright 2012 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.
 
 #include "src/v8.h"
 
 #include "src/hydrogen.h"
 #include "src/lithium-inl.h"
 #include "src/lithium-allocator-inl.h"
 #include "src/string-stream.h"
@@ skipping 2156 matching lines @@
       allocator_(allocator) {
   if (FLAG_hydrogen_stats) {
     allocator_zone_start_allocation_size_ =
         allocator->zone()->allocation_size();
   }
 }
 
 
 LAllocatorPhase::~LAllocatorPhase() {
   if (FLAG_hydrogen_stats) {
-    unsigned size = allocator_->zone()->allocation_size() -
-                    allocator_zone_start_allocation_size_;
+    size_t size = allocator_->zone()->allocation_size() -
+                  allocator_zone_start_allocation_size_;
     isolate()->GetHStatistics()->SaveTiming(name(), base::TimeDelta(), size);
   }
 
   if (ShouldProduceTraceOutput()) {
     isolate()->GetHTracer()->TraceLithium(name(), allocator_->chunk());
     isolate()->GetHTracer()->TraceLiveRanges(name(), allocator_);
   }
 
 #ifdef DEBUG
   if (allocator_ != NULL) allocator_->Verify();
 #endif
 }
 
 
 } }  // namespace v8::internal