1. A small fix of Windows VM size.

third_party/tcmalloc/chromium/src/common.cc

 // Copyright (c) 2008, Google Inc.
 // All rights reserved.
 // 
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 // 
 //     * Redistributions of source code must retain the above copyright
 // notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
@@ skipping 175 matching lines @@
   }
 
   // Initialize the num_objects_to_move array.
   for (size_t cl = 1; cl  < kNumClasses; ++cl) {
     num_objects_to_move_[cl] = NumMoveSize(ByteSizeForClass(cl));
   }
 }
 
 // Metadata allocator -- keeps stats about how many bytes allocated.
 static uint64_t metadata_system_bytes_ = 0;
+static uint64_t metadata_unmapped_bytes_ = 0;
+
 void* MetaDataAlloc(size_t bytes) {
   static size_t pagesize;
 #ifdef HAVE_GETPAGESIZE
   if (pagesize == 0)
     pagesize = getpagesize();
 #endif
 
   void* result = TCMalloc_SystemAlloc(bytes, NULL, pagesize);
   if (result != NULL) {
     metadata_system_bytes_ += bytes;
   }
   return result;
 }
 
 uint64_t metadata_system_bytes() { return metadata_system_bytes_; }
+uint64_t metadata_unmapped_bytes() { return metadata_unmapped_bytes_; }
 
-void increment_metadata_system_bytes(size_t bytes) {
-  metadata_system_bytes_ += bytes;
+void update_metadata_system_bytes(int diff) {
+  metadata_system_bytes_ += diff;
+}
+void update_metadata_unmapped_bytes(int diff) {
+  metadata_unmapped_bytes_ += diff;
 }
 
 }  // namespace tcmalloc