Add HDMI-CEC service

This CL adds a system service handling HDMI-CEC protocol. The service
is equipped with the capability sending/receiving HDMI-CEC messages

Not all the messages are in place. Currently it has messages to support
a few features only, as follows:

- One touch play
- System information
- Routing control (partially - active source status maintenance only)
- Device OSD transfer
- Power status

It will be extended to cover the wider usages in the follow up CLs.

The CEC standard version referenced in the implementation is 1.3a.

Change-Id: Ifed0b02f52ebf098eddb3bd0987efbf353b7e8fe

services/java/com/android/server/SystemServer.java

@@ -114,6 +114,8 @@ public final class SystemServer {
             "com.android.server.print.PrintManagerService";
     private static final String USB_SERVICE_CLASS =
             "com.android.server.usb.UsbService$Lifecycle";
+    private static final String HDMI_CEC_SERVICE_CLASS =
+            "com.android.server.hdmi.HdmiCecService";
 
     private final int mFactoryTestMode;
     private Timer mProfilerSnapshotTimer;
@@ -887,6 +889,12 @@ public final class SystemServer {
                 reportWtf("starting Print Service", e);
             }
 
+            try {
+                mSystemServiceManager.startService(HDMI_CEC_SERVICE_CLASS);
+            } catch (Throwable e) {
+                reportWtf("starting HdmiCec Service", e);
+            }
+
             if (!disableNonCoreServices) {
                 try {
                     Slog.i(TAG, "Media Router Service");