Move KeyLayoutMap from RefBase to shared_ptr.

Move KeyLayoutMap from inheriting RefBase and use shared_ptr
to store in owner class like KeyMap.

Bug: 160010896

Test: atest inputflinger, atest libinput_tests
Change-Id: I565e07bdc501af644df5ebb8388fce10af185bce
diff --git a/include/input/Keyboard.h b/include/input/Keyboard.h
index 92da10c..4c56a69 100644
--- a/include/input/Keyboard.h
+++ b/include/input/Keyboard.h
@@ -34,7 +34,7 @@
 class KeyMap {
 public:
     std::string keyLayoutFile;
-    sp<KeyLayoutMap> keyLayoutMap;
+    std::shared_ptr<KeyLayoutMap> keyLayoutMap;
 
     std::string keyCharacterMapFile;
     sp<KeyCharacterMap> keyCharacterMap;