Mandate unique_ptr for base::IDMap in IDMapOwnPointer mode.

chrome/browser/metrics/subprocess_metrics_provider.cc

Index: chrome/browser/metrics/subprocess_metrics_provider.cc
diff --git a/chrome/browser/metrics/subprocess_metrics_provider.cc b/chrome/browser/metrics/subprocess_metrics_provider.cc
index 06d255350adeb91f8c594192be5dd1689f8b7743..68c034b5b92b645f7e99767ede45af4ec6d8c264 100644
--- a/chrome/browser/metrics/subprocess_metrics_provider.cc
+++ b/chrome/browser/metrics/subprocess_metrics_provider.cc
@@ -59,7 +59,9 @@ void SubprocessMetricsProvider::RegisterSubprocessAllocator(
     return;
 
   // Map is "MapOwnPointer" so transfer ownership to it.
-  allocators_by_id_.AddWithID(allocator.release(), id);
+  allocators_by_id_.AddWithID(
+      std::unique_ptr<base::PersistentHistogramAllocator>(
+          allocator.release()), id);
 }
 
 void SubprocessMetricsProvider::DeregisterSubprocessAllocator(int id) {