Port Signal's emoji implementation to Briar

Add functionality to save and restore recently used Emojis

Update emoji and add new categories based on AOSP's XML file

briar-android/src/org/thoughtcrime/securesms/components/RepeatableImageKey.java

@@ -0,0 +1,95 @@
+package org.thoughtcrime.securesms.components;
+
+import android.content.Context;
+import android.os.Build.VERSION;
+import android.os.Build.VERSION_CODES;
+import android.support.annotation.UiThread;
+import android.util.AttributeSet;
+import android.view.HapticFeedbackConstants;
+import android.view.MotionEvent;
+import android.view.View;
+import android.view.ViewConfiguration;
+import android.widget.ImageButton;
+
+@UiThread
+public class RepeatableImageKey extends ImageButton {
+
+	private KeyEventListener listener;
+
+	public RepeatableImageKey(Context context) {
+		super(context);
+		init();
+	}
+
+	public RepeatableImageKey(Context context, AttributeSet attrs) {
+		super(context, attrs);
+		init();
+	}
+
+	public RepeatableImageKey(Context context, AttributeSet attrs,
+			int defStyleAttr) {
+		super(context, attrs, defStyleAttr);
+		init();
+	}
+
+	private void init() {
+		setOnClickListener(new RepeaterClickListener());
+		setOnTouchListener(new RepeaterTouchListener());
+	}
+
+	public void setOnKeyEventListener(KeyEventListener listener) {
+		this.listener = listener;
+	}
+
+	private void notifyListener() {
+		if (this.listener != null) this.listener.onKeyEvent();
+	}
+
+	private class RepeaterClickListener implements OnClickListener {
+		@Override
+		public void onClick(View v) {
+			notifyListener();
+		}
+	}
+
+	private class Repeater implements Runnable {
+		@Override
+		public void run() {
+			notifyListener();
+			postDelayed(this, VERSION.SDK_INT >= VERSION_CODES.HONEYCOMB_MR1
+					? ViewConfiguration.getKeyRepeatDelay()
+					: 50);
+		}
+	}
+
+	private class RepeaterTouchListener implements OnTouchListener {
+		private Repeater repeater;
+
+		private RepeaterTouchListener() {
+			this.repeater = new Repeater();
+		}
+
+		@Override
+		public boolean onTouch(View view, MotionEvent motionEvent) {
+			switch (motionEvent.getAction()) {
+				case MotionEvent.ACTION_DOWN:
+					view.postDelayed(repeater,
+							VERSION.SDK_INT >= VERSION_CODES.HONEYCOMB_MR1
+									? ViewConfiguration.getKeyRepeatTimeout()
+									: ViewConfiguration.getLongPressTimeout());
+					performHapticFeedback(HapticFeedbackConstants.KEYBOARD_TAP);
+					return false;
+				case MotionEvent.ACTION_CANCEL:
+				case MotionEvent.ACTION_UP:
+					view.removeCallbacks(repeater);
+					return false;
+				default:
+					return false;
+			}
+		}
+	}
+
+	public interface KeyEventListener {
+		void onKeyEvent();
+	}
+}