platform2: Enforce virtual destructors on base classes There have been a number of memory leak issues due to absence of virtual destructors on base classes. Swept through the following targets: buffet, libchromeos, webserver. For every class defined, I did one of the following three things: 1. If the class is not meant to be derived from, marked it as 'final'. 2. If classes derived from a particular base class are not meant to be deleted through the base class, marked the base class's destructor as 'protected'. 3. Otherwise made the base class's destructor virtual. BUG=None TEST=`FEATURES=test emerge-link libchromeos webserver buffet` Change-Id: I4d909399896d025c39980c9546b79b145614fc47 Reviewed-on: https://chromium-review.googlesource.com/273000 Trybot-Ready: Alex Vakulenko <avakulenko@chromium.org> Tested-by: Alex Vakulenko <avakulenko@chromium.org> Reviewed-by: Vitaly Buka <vitalybuka@chromium.org> Commit-Queue: Vitaly Buka <vitalybuka@chromium.org>

diff --git a/buffet/base_api_handler.cc b/buffet/base_api_handler.cc
index ce08bd1..69ed67c 100644
--- a/buffet/base_api_handler.cc
+++ b/buffet/base_api_handler.cc

@@ -14,7 +14,7 @@
 
 // Helps to get parameters from native_types::Object representing
 // CommandInstance parameters.
-class ParametersReader {
+class ParametersReader final {
  public:
   explicit ParametersReader(const native_types::Object* parameters)
       : parameters_{parameters} {}

diff --git a/buffet/buffet_client.cc b/buffet/buffet_client.cc
index ef4bf03..8408a46 100644
--- a/buffet/buffet_client.cc
+++ b/buffet/buffet_client.cc

@@ -139,7 +139,7 @@
   return val;
 }
 
-class Daemon : public chromeos::DBusDaemon {
+class Daemon final : public chromeos::DBusDaemon {
  public:
   Daemon() = default;
 

diff --git a/buffet/commands/command_definition.h b/buffet/commands/command_definition.h
index 3328a94..a5e2916 100644
--- a/buffet/commands/command_definition.h
+++ b/buffet/commands/command_definition.h

@@ -19,7 +19,7 @@
 // constraints. See comments for CommandDefinitions::LoadCommands for the
 // detailed description of what command categories are and what they are used
 // for.
-class CommandDefinition {
+class CommandDefinition final {
  public:
   struct Visibility {
     Visibility() = default;

diff --git a/buffet/commands/command_dictionary.h b/buffet/commands/command_dictionary.h
index 7668fba..97ab596 100644
--- a/buffet/commands/command_dictionary.h
+++ b/buffet/commands/command_dictionary.h

@@ -30,7 +30,7 @@
 // the map) is a compound name in a form of "package_name.command_name",
 // where "package_name" is a name of command package such as "base", "printers",
 // and others. So the full command name could be "base.reboot", for example.
-class CommandDictionary {
+class CommandDictionary final {
  public:
   CommandDictionary() = default;
 

diff --git a/buffet/commands/command_queue.h b/buffet/commands/command_queue.h
index 9178c8a..db6707c 100644
--- a/buffet/commands/command_queue.h
+++ b/buffet/commands/command_queue.h

@@ -66,7 +66,7 @@
   // Returns current time.
   base::Time Now() const;
 
-  // Overrided value to be returned from Now().
+  // Overridden value to be returned from Now().
   base::Time test_now_;
 
   // ID-to-CommandInstance map.

diff --git a/buffet/commands/dbus_command_dispatcher.h b/buffet/commands/dbus_command_dispatcher.h
index ab63a6c..e9f5003 100644
--- a/buffet/commands/dbus_command_dispatcher.h
+++ b/buffet/commands/dbus_command_dispatcher.h

@@ -28,7 +28,7 @@
 // update the command handling progress. Once command is handled,
 // DBusCommandProxy::Done() is called and the command is removed from the
 // command queue and D-Bus ExportedObjectManager.
-class DBusCommandDispacher {
+class DBusCommandDispacher final {
  public:
   explicit DBusCommandDispacher(const base::WeakPtr<
       chromeos::dbus_utils::ExportedObjectManager>& object_manager);

diff --git a/buffet/commands/schema_utils.h b/buffet/commands/schema_utils.h
index 625b854..59e3b39 100644
--- a/buffet/commands/schema_utils.h
+++ b/buffet/commands/schema_utils.h

@@ -43,7 +43,7 @@
 // is inherited or overridden, while |is_inherited| can be used to identify
 // if the attribute was inherited (true) or overridden (false).
 template<typename T>
-class InheritableAttribute {
+class InheritableAttribute final {
  public:
   InheritableAttribute() = default;
   explicit InheritableAttribute(T val)

diff --git a/buffet/device_registration_info.h b/buffet/device_registration_info.h
index 7732da4..1314d5f 100644
--- a/buffet/device_registration_info.h
+++ b/buffet/device_registration_info.h

@@ -55,7 +55,7 @@
       const std::shared_ptr<chromeos::http::Transport>& transport,
       bool notifications_enabled);
 
-  virtual ~DeviceRegistrationInfo();
+  ~DeviceRegistrationInfo() override;
 
   // Add callback to listen for changes in registration status.
   void AddOnRegistrationChangedCallback(

diff --git a/buffet/main.cc b/buffet/main.cc
index a4ecf59..c7d44d0 100644
--- a/buffet/main.cc
+++ b/buffet/main.cc

@@ -21,7 +21,7 @@
 
 namespace buffet {
 
-class Daemon : public DBusServiceDaemon {
+class Daemon final : public DBusServiceDaemon {
  public:
   Daemon(const base::FilePath& config_path,
          const base::FilePath& state_path,

diff --git a/buffet/notification/xmpp_channel.h b/buffet/notification/xmpp_channel.h
index 8db127e..4afb5df 100644
--- a/buffet/notification/xmpp_channel.h
+++ b/buffet/notification/xmpp_channel.h

@@ -31,7 +31,7 @@
   XmppChannel(const std::string& account,
               const std::string& access_token,
               const scoped_refptr<base::TaskRunner>& task_runner);
-  virtual ~XmppChannel() = default;
+  ~XmppChannel() override = default;
 
   // Overrides from NotificationChannel.
   std::string GetName() const override;

diff --git a/buffet/notification/xmpp_stream_parser.h b/buffet/notification/xmpp_stream_parser.h
index 6bb39c7..9ff9200 100644
--- a/buffet/notification/xmpp_stream_parser.h
+++ b/buffet/notification/xmpp_stream_parser.h

@@ -47,6 +47,9 @@
         std::map<std::string, std::string> attributes) = 0;
     virtual void OnStreamEnd(const std::string& node_name) = 0;
     virtual void OnStanza(std::unique_ptr<XmlNode> stanza) = 0;
+
+   protected:
+    virtual ~Delegate() = default;
   };
 
   explicit XmppStreamParser(Delegate* delegate);

diff --git a/buffet/storage_impls.h b/buffet/storage_impls.h
index 7f205da..6bdf251 100644
--- a/buffet/storage_impls.h
+++ b/buffet/storage_impls.h

@@ -17,7 +17,7 @@
 class FileStorage : public StorageInterface {
  public:
   explicit FileStorage(const base::FilePath& file_path);
-  virtual ~FileStorage() = default;
+  ~FileStorage() override = default;
   std::unique_ptr<base::DictionaryValue> Load() override;
   bool Save(const base::DictionaryValue& config) override;
 
@@ -30,7 +30,7 @@
 class MemStorage : public StorageInterface {
  public:
   MemStorage() = default;
-  virtual ~MemStorage() = default;
+  ~MemStorage() override = default;
   std::unique_ptr<base::DictionaryValue> Load() override;
   bool Save(const base::DictionaryValue& config) override;
 

diff --git a/buffet/test_daemon/main.cc b/buffet/test_daemon/main.cc
index 0da72c2..64c0c00 100644
--- a/buffet/test_daemon/main.cc
+++ b/buffet/test_daemon/main.cc

@@ -72,7 +72,7 @@
 
 }  // anonymous namespace
 
-class Daemon : public chromeos::DBusDaemon {
+class Daemon final : public chromeos::DBusDaemon {
  public:
   Daemon() = default;