Stop BackBuffer being so lazy.

We now need it to exist independently of anything requesting it,
otherwise we miss lines being added.

src/com/dmdirc/Channel.java

@@ -143,6 +143,7 @@ public class Channel extends MessageTarget implements GroupChat {
 
         eventHandler = new ChannelEventHandler(this, getEventBus(), groupChatUserManager);
 
+        initBackBuffer();
         registerCallbacks();
         updateTitle();
         selfJoin();

src/com/dmdirc/CustomWindow.java

@@ -48,6 +48,7 @@ public class CustomWindow extends FrameContainer {
         super(parent, "custom", name, title, parent.getConfigManager(), backBufferFactory,
                 urlBuilder, parent.getEventBus(),
                 Collections.singletonList(WindowComponent.TEXTAREA.getIdentifier()));
+        initBackBuffer();
     }
 
     /**
@@ -62,6 +63,7 @@ public class CustomWindow extends FrameContainer {
             final BackBufferFactory backBufferFactory) {
         super(null, "custom", name, title, configProvider, backBufferFactory, urlBuilder,
                 eventBus, Collections.singletonList(WindowComponent.TEXTAREA.getIdentifier()));
+        initBackBuffer();
     }
 
     @Override

src/com/dmdirc/FrameContainer.java

@@ -100,8 +100,6 @@ public abstract class FrameContainer {
     private final BackBufferFactory backBufferFactory;
     /** The back buffer for this container. */
     private BackBuffer backBuffer;
-    /** Lock for access to {@link #backBuffer}. */
-    private final Object backBufferLock = new Object();
 
     /**
      * The command parser used for commands in this container.
@@ -196,6 +194,11 @@ public abstract class FrameContainer {
         setIcon(icon);
     }
 
+    protected void initBackBuffer() {
+        backBuffer = backBufferFactory.getBackBuffer(this);
+        backBuffer.startAddingEvents();
+    }
+
     public Optional<FrameContainer> getParent() {
         return parent;
     }
@@ -391,13 +394,6 @@ public abstract class FrameContainer {
      * @return This container's back buffer.
      */
     public BackBuffer getBackBuffer() {
-        synchronized (backBufferLock) {
-            if (backBuffer == null) {
-                backBuffer = backBufferFactory.getBackBuffer(this);
-                backBuffer.startAddingEvents();
-            }
-        }
-
         return backBuffer;
     }
 

src/com/dmdirc/GlobalWindow.java

@@ -61,6 +61,7 @@ public class GlobalWindow extends FrameContainer {
                 messageSinkManager, eventBus,
                 Arrays.asList(WindowComponent.TEXTAREA.getIdentifier(),
                         WindowComponent.INPUTFIELD.getIdentifier()));
+        initBackBuffer();
     }
 
     @Override

src/com/dmdirc/Query.java

@@ -101,6 +101,7 @@ public class Query extends MessageTarget implements PrivateActionListener,
         this.server = newServer;
         this.user = user;
         updateTitle();
+        initBackBuffer();
     }
 
     @Override

src/com/dmdirc/Server.java

@@ -240,6 +240,7 @@ public class Server extends FrameContainer implements Connection {
         getConfigManager().addChangeListener("formatter", "serverName", configListener);
         getConfigManager().addChangeListener("formatter", "serverTitle", configListener);
 
+        initBackBuffer();
         this.highlightManager = new HighlightManager(getConfigManager(),
                 new ColourManager(getConfigManager(), getEventBus()));
         highlightManager.init();