allow to bind volume keys

Author: Ishan09811

src/pandroid/app/src/main/java/com/panda3ds/pandroid/app/GameActivity.java

@@ -151,11 +151,7 @@ protected void onPause() {
 	}
 
 	@Override
-	public boolean dispatchKeyEvent(KeyEvent event) {
-		if (event.getKeyCode() == KeyEvent.KEYCODE_VOLUME_UP || event.getKeyCode() == KeyEvent.KEYCODE_VOLUME_DOWN) {
-                    return super.dispatchKeyEvent(event);
-		}
-		
+	public boolean dispatchKeyEvent(KeyEvent event) {	
 		if ((!drawerFragment.isOpened()) && InputHandler.processKeyEvent(event)) {
 			return true;
 		}

src/pandroid/app/src/main/java/com/panda3ds/pandroid/input/InputHandler.java

@@ -110,6 +110,10 @@ public static boolean processKeyEvent(KeyEvent event) {
             }
         }
         String code = KeyEvent.keyCodeToString(event.getKeyCode());
+        if (InputMap.relative(code) == KeyName.NULL) {
+            return false;
+        }
+
         if (event.getAction() == KeyEvent.ACTION_UP) {
             keyDownEvents.remove(code);
             handleEvent(new InputEvent(code, 0.0f));