MTP: Add support for device property changed events

Also fixed bug in MtpProperty::write() for device properties

Bug: 7342482
Change-Id: If0099095d101409d131564e55b1939895c69c202
diff --git a/media/mtp/MtpServer.cpp b/media/mtp/MtpServer.cpp
index df87db4..dadfb54 100644
--- a/media/mtp/MtpServer.cpp
+++ b/media/mtp/MtpServer.cpp
@@ -93,6 +93,7 @@
     MTP_EVENT_OBJECT_REMOVED,
     MTP_EVENT_STORE_ADDED,
     MTP_EVENT_STORE_REMOVED,
+    MTP_EVENT_DEVICE_PROP_CHANGED,
 };
 
 MtpServer::MtpServer(int fd, MtpDatabase* database, bool ptp,
@@ -261,6 +262,11 @@
     sendEvent(MTP_EVENT_STORE_REMOVED, id);
 }
 
+void MtpServer::sendDevicePropertyChanged(MtpDeviceProperty property) {
+    ALOGV("sendDevicePropertyChanged %d\n", property);
+    sendEvent(MTP_EVENT_DEVICE_PROP_CHANGED, property);
+}
+
 void MtpServer::sendEvent(MtpEventCode code, uint32_t param1) {
     if (mSessionOpen) {
         mEvent.setEventCode(code);