Move KeyCharacterMap from RefBase to shared_ptr.

Move KeyCharacterMap from RefBase and make it shared_ptr in EventHub
device when loaded from file.
A shared_ptr of KeyCharacterMap is returned by EventHub getKeyCharacterMap
to be shared in InputdeviceInfo.
Remove extra KeyCharacterMap in EventHub to save memory sapce.

Bug: 160010896
Test: atest inputflinger, atest libinput_tests

Change-Id: Ibb317ea0684e6af6e7a6d808f816fc4a05c7b421
diff --git a/libs/input/Keyboard.cpp b/libs/input/Keyboard.cpp
index 1a64a9c..38a68b3 100644
--- a/libs/input/Keyboard.cpp
+++ b/libs/input/Keyboard.cpp
@@ -127,12 +127,12 @@
         return NAME_NOT_FOUND;
     }
 
-    status_t status = KeyCharacterMap::load(path,
-            KeyCharacterMap::FORMAT_BASE, &keyCharacterMap);
-    if (status) {
-        return status;
+    base::Result<std::shared_ptr<KeyCharacterMap>> ret =
+            KeyCharacterMap::load(path, KeyCharacterMap::FORMAT_BASE);
+    if (!ret) {
+        return ret.error().code();
     }
-
+    keyCharacterMap = *ret;
     keyCharacterMapFile = path;
     return OK;
 }