Replace scoped_ptr With std::unique_ptr

(This is a merge of http://go/wvgerrit/65782)

We have had our own scoped_ptr implementation that is used throughout
the codebase. Now that we support C++11, we can replace these with
std::unique_ptr.

Doing this replacement exposed a few places where the two were not
interchangeable. OEMCrypto Ref was doing some unsafe things with passing
scoped_ptrs to functions and has been updated to use move semantics. And
a few constructors were explicitly constructing a scoped_ptr with NULL,
which is ambiguous with std::unique_ptr. These have been replaced with
default constructor calls.

Bug: 111851141
Test: CE CDM Unit Tests
Test: Android Unit Tests
Change-Id: I37d6d7aad4906709381c74f0c5439f826d2be768

libwvdrmengine/cdm/core/include/cdm_session.h

@@ -5,6 +5,7 @@
 #ifndef WVCDM_CORE_CDM_SESSION_H_
 #define WVCDM_CORE_CDM_SESSION_H_
 
+#include <memory>
 #include <set>
 #include <string>
 #include <vector>
@@ -18,7 +19,6 @@
 #include "metrics_collections.h"
 #include "oemcrypto_adapter.h"
 #include "policy_engine.h"
-#include "scoped_ptr.h"
 #include "timer_metric.h"
 #include "wv_cdm_types.h"
 
@@ -228,10 +228,10 @@ class CdmSession {
   bool closed_;  // Session closed, but final shared_ptr has not been released.
   CdmSessionId session_id_;
   FileSystem* file_system_;
-  scoped_ptr<CdmLicense> license_parser_;
-  scoped_ptr<CryptoSession> crypto_session_;
-  scoped_ptr<PolicyEngine> policy_engine_;
-  scoped_ptr<DeviceFiles> file_handle_;
+  std::unique_ptr<CdmLicense> license_parser_;
+  std::unique_ptr<CryptoSession> crypto_session_;
+  std::unique_ptr<PolicyEngine> policy_engine_;
+  std::unique_ptr<DeviceFiles> file_handle_;
   bool license_received_;
   bool is_offline_;
   bool is_release_;