Make ISecurityManagerListener into abstract class

Bug: 143169747
Bug: 142341141
Change-Id: I67ef0d20c6cbd0289cce30389a0bd505e5fc1552
diff --git a/gd/security/security_manager.cc b/gd/security/security_manager.cc
index da2b30b..239f388 100644
--- a/gd/security/security_manager.cc
+++ b/gd/security/security_manager.cc
@@ -21,6 +21,9 @@
 
 using namespace bluetooth::security;
 
+// Definition of Pure Virtual Destructor
+ISecurityManagerListener::~ISecurityManagerListener() {}
+
 void SecurityManager::Init() {
   security_handler_->Post(
       common::BindOnce(&internal::SecurityManagerImpl::Init, common::Unretained(security_manager_impl_)));
diff --git a/gd/security/security_manager.h b/gd/security/security_manager.h
index 6ccdd6e..1fbca95 100644
--- a/gd/security/security_manager.h
+++ b/gd/security/security_manager.h
@@ -34,28 +34,28 @@
 class ISecurityManagerListener {
  public:
   ISecurityManagerListener(os::Handler* handler) : handler_(handler) {}
-  virtual ~ISecurityManagerListener() = default;
+  virtual ~ISecurityManagerListener() = 0;
 
   /**
    * Called when a device is successfully bonded.
    *
    * @param device pointer to the bonded device
    */
-  virtual void OnDeviceBonded(std::shared_ptr<bluetooth::hci::Device> device);
+  virtual void OnDeviceBonded(std::shared_ptr<bluetooth::hci::Device> device) = 0;
 
   /**
    * Called when a device is successfully un-bonded.
    *
    * @param device pointer to the device that is no longer bonded
    */
-  virtual void OnDeviceUnbonded(std::shared_ptr<bluetooth::hci::Device> device);
+  virtual void OnDeviceUnbonded(std::shared_ptr<bluetooth::hci::Device> device) = 0;
 
   /**
    * Called as a result of a failure during the bonding process.
    *
    * @param device pointer to the device that is no longer bonded
    */
-  virtual void OnDeviceBondFailed(std::shared_ptr<bluetooth::hci::Device> device);
+  virtual void OnDeviceBondFailed(std::shared_ptr<bluetooth::hci::Device> device) = 0;
 
   bool operator==(const ISecurityManagerListener& rhs) const {
     return &*this == &rhs;