Convert //components/proximity_auth from scoped_ptr to std::unique_ptr

components/proximity_auth/webui/reachable_phone_flow.h

Index: components/proximity_auth/webui/reachable_phone_flow.h
diff --git a/components/proximity_auth/webui/reachable_phone_flow.h b/components/proximity_auth/webui/reachable_phone_flow.h
index 211017d9602718f1c39a026a217318714cc79295..e5df1e617266f504a482a75505e0c96a1f681b72 100644
--- a/components/proximity_auth/webui/reachable_phone_flow.h
+++ b/components/proximity_auth/webui/reachable_phone_flow.h
@@ -5,12 +5,12 @@
 #ifndef COMPONENTS_PROXIMITY_AUTH_WEBUI_REACHABLE_PHONE_FLOW_H_
 #define COMPONENTS_PROXIMITY_AUTH_WEBUI_REACHABLE_PHONE_FLOW_H_
 
+#include <memory>
 #include <string>
 #include <vector>
 
 #include "base/callback.h"
 #include "base/macros.h"
-#include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 
 namespace cryptauth {
@@ -68,7 +68,7 @@ class ReachablePhoneFlow {
   ReachablePhonesCallback callback_;
 
   // The client making the current CryptAuth API call.
-  scoped_ptr<CryptAuthClient> client_;
+  std::unique_ptr<CryptAuthClient> client_;
 
   base::WeakPtrFactory<ReachablePhoneFlow> weak_ptr_factory_;