Merge AOSP android-9.0.0_r3

Fix conflicts and make it build in 5.1, 6.0, 7.1, 8.1, and 9.0

Change-Id: Ida0a64c29ff27d339b7f42a18d820930964ac6e4
diff --git a/legacy_property_service.cpp b/legacy_property_service.cpp
index 90a0d47..c3990f7 100644
--- a/legacy_property_service.cpp
+++ b/legacy_property_service.cpp
@@ -40,11 +40,8 @@
 #define INT32_MAX	(2147483647)
 #endif
 
-static int persistent_properties_loaded = 0;
 static int property_area_inited = 0;
 
-static int property_set_fd = -1;
-
 typedef struct {
     void *data;
     size_t size;
@@ -203,7 +200,7 @@
     *sz = pa_workspace.size;
 }
 
-static void copy_property_to_legacy(const char *key, const char *value, void *cookie)
+static void copy_property_to_legacy(const char *key, const char *value, void *cookie __unused)
 {
     legacy_property_set(key, value);
 }