graphics: Add composer 2.3

The 2.3 interface adds IComposerClient.getDisplayIdentificationData,
which enables display identification for generalized multi-display
support.

Bug: 74619554
Test: VtsHalGraphicsComposerV2_3TargetTest
Change-Id: I303e722ce938fe0af4fc77da812e3525d8c90251
diff --git a/graphics/composer/2.3/IComposer.hal b/graphics/composer/2.3/IComposer.hal
new file mode 100644
index 0000000..90b2427
--- /dev/null
+++ b/graphics/composer/2.3/IComposer.hal
@@ -0,0 +1,37 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.hardware.graphics.composer@2.3;
+
+import IComposerClient;
+
+import @2.1::Error;
+import @2.2::IComposer;
+
+interface IComposer extends @2.2::IComposer {
+
+    /**
+     * Creates a v2.3 client of the composer. Supersedes @2.1::createClient.
+     *
+     * @return error is NONE upon success. Otherwise,
+     *         NO_RESOURCES when the client could not be created.
+     * @return client is the newly created client.
+     */
+    @entry
+    @callflow(next="*")
+    createClient_2_3() generates (Error error, IComposerClient client);
+
+};