Reduce memory usage in DelayedPersistentAllocation.

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 f569efa5fd353d9ea18141202a130091129665cd..b46dcfa3b5ff0a7972f7d854ed57f386350ac1fc 100644
--- a/base/metrics/persistent_memory_allocator.cc
+++ b/base/metrics/persistent_memory_allocator.cc
@@ -18,6 +18,7 @@
 #include "base/memory/shared_memory.h"
 #include "base/metrics/histogram_macros.h"
 #include "base/metrics/sparse_histogram.h"
+#include "base/numerics/safe_conversions.h"
 #include "base/threading/thread_restrictions.h"
 
 namespace {
@@ -1123,8 +1124,8 @@ DelayedPersistentAllocation::DelayedPersistentAllocation(
     bool make_iterable)
     : allocator_(allocator),
       type_(type),
-      size_(size),
-      offset_(offset),
+      size_(checked_cast<uint32_t>(size)),
+      offset_(checked_cast<uint32_t>(offset)),
       make_iterable_(make_iterable),
       reference_(ref) {
   DCHECK(allocator_);