Initial Android Auto External View Systems drivers

Add support for EVS system camera and display drivers.
These build and run but still contain significant placeholder code and
TODO items.

Bug: 32095143
Test:  run against evs_test (submitted in future change set)
Change-Id: I9187e888f03248e5cd43293253dc76a71184c02d
diff --git a/evs/1.0/IEvsEnumerator.hal b/evs/1.0/IEvsEnumerator.hal
new file mode 100644
index 0000000..e3a1382
--- /dev/null
+++ b/evs/1.0/IEvsEnumerator.hal
@@ -0,0 +1,71 @@
+/*
+ * Copyright (C) 2016 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.evs@1.0;
+
+import types;
+import IEvsCamera;
+import IEvsDisplay;
+
+
+/**
+ * Provides the mechanism for EVS camera discovery
+ */
+interface IEvsEnumerator {
+
+    /**
+     * Returns a list of all EVS cameras available to the system
+     */
+    getCameraList() generates (vec<CameraDesc> cameras);
+
+
+    /**
+     * Get the IEvsCamera associated with a cameraId from a CameraDesc
+     *
+     * Given a camera's unique cameraId from ca CameraDesc, returns
+     * the ICamera interface assocaited with the specified camera.
+     * When done using the camera, it must be returned by calling
+     * closeCamera on the ICamera interface.
+     */
+    openCamera(string cameraId) generates (IEvsCamera carCamera);
+
+    /**
+     * Return the specified IEvsCamera interface as no longer in use
+     *
+     * When the IEvsCamera object is no longer required, it must be released.
+     * NOTE: Video streaming must be cleanly stopped before making this call.
+     */
+    closeCamera(IEvsCamera carCamera);
+
+
+    /**
+     * Get exclusive access to IEvsDisplay for the system
+     *
+     * There can be at most one EVS display object for the system and this function
+     * requests access to it. If the EVS display is not available or is already in use,
+     * a null pointer is returned.
+     */
+    openDisplay() generates (IEvsDisplay display);
+
+    /**
+     * Return the specified IEvsDisplay interface as no longer in use
+     *
+     * When the IEvsDisplay object is no longer required, it must be released.
+     * NOTE: All buffer must have been returned to the display before making this call.
+     */
+    closeDisplay(IEvsDisplay display);
+};
+