thermal: IThermal V1.1, add methods to send thermal throttling events

Add IThermalCallback and IThermal::registerThermalCallback() method.
Frameworks code calls this method to register a callback used by the
IThermal HAL implementation to send thermal events to the framework
ThermalService.

Bug: 30982366
Test: VtsHalThermalV1_1Target on marlin
      manual test on marlin using marlin 1.1 HAL with modified
      thermal-engine.conf and temporary debug code for notification
Change-Id: Ib49ad93a9495e3af515fced4e46f20186661fe07
diff --git a/thermal/1.1/IThermal.hal b/thermal/1.1/IThermal.hal
new file mode 100644
index 0000000..14f35ba
--- /dev/null
+++ b/thermal/1.1/IThermal.hal
@@ -0,0 +1,31 @@
+/*
+ * Copyright (C) 2017 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.thermal@1.1;
+
+import android.hardware.thermal@1.0::IThermal;
+import IThermalCallback;
+
+interface IThermal extends @1.0::IThermal {
+   /**
+    * Register an IThermalCallback, used by the Thermal HAL
+    * to send thermal events to the framework thermal service.
+    *
+    * @param callback the IThermalCallback to use for sending
+    *        thermal events, or nullptr to set no callback
+    */
+    registerThermalCallback(IThermalCallback callback);
+};