Disable file operations on NACL builds.

base/metrics/persistent_memory_allocator.cc

Index: base/metrics/persistent_memory_allocator.cc
diff --git a/base/metrics/persistent_memory_allocator.cc b/base/metrics/persistent_memory_allocator.cc
index ee668233cf96b176d8962460ecd50054b6d5fec0..1c20143bff211d03145e282871ee0f323af2e1d0 100644
--- a/base/metrics/persistent_memory_allocator.cc
+++ b/base/metrics/persistent_memory_allocator.cc
@@ -754,6 +754,7 @@ bool SharedPersistentMemoryAllocator::IsSharedMemoryAcceptable(
 }
 
 
+#if !defined(OS_NACL)
 //----- FilePersistentMemoryAllocator ------------------------------------------
 
 FilePersistentMemoryAllocator::FilePersistentMemoryAllocator(
@@ -778,5 +779,6 @@ bool FilePersistentMemoryAllocator::IsFileAcceptable(
     bool read_only) {
   return IsMemoryAcceptable(file.data(), file.length(), 0, read_only);
 }
+#endif  // !defined(OS_NACL)
 
 }  // namespace base