Make VehicleUnit @SystemApi.
am: 6817673468

Change-Id: Ib51a9dfceede9cb693bc517236e1be0e182b947e
diff --git a/car-lib/api/system-current.txt b/car-lib/api/system-current.txt
index 1adaae7..94bf4b8 100644
--- a/car-lib/api/system-current.txt
+++ b/car-lib/api/system-current.txt
@@ -151,6 +151,38 @@
     field public static final int WRITE = 2; // 0x2
   }
 
+  public final class VehicleUnit {
+    field public static final int AMPERE_HOURS = 100; // 0x64
+    field public static final int BAR = 114; // 0x72
+    field public static final int CELSIUS = 48; // 0x30
+    field public static final int DEGREES = 128; // 0x80
+    field public static final int FAHRENHEIT = 49; // 0x31
+    field public static final int HERTZ = 3; // 0x3
+    field public static final int IMPERIAL_GALLON = 67; // 0x43
+    field public static final int KELVIN = 50; // 0x32
+    field public static final int KILOMETER = 35; // 0x23
+    field public static final int KILOPASCAL = 112; // 0x70
+    field public static final int KILOWATT_HOUR = 101; // 0x65
+    field public static final int LITER = 65; // 0x41
+    field public static final int METER = 33; // 0x21
+    field public static final int METER_PER_SEC = 1; // 0x1
+    field public static final int MILE = 36; // 0x24
+    field public static final int MILLIAMPERE = 97; // 0x61
+    field public static final int MILLILITER = 64; // 0x40
+    field public static final int MILLIMETER = 32; // 0x20
+    field public static final int MILLIVOLT = 98; // 0x62
+    field public static final int MILLIWATTS = 99; // 0x63
+    field public static final int NANO_SECS = 80; // 0x50
+    field public static final int PERCENTILE = 16; // 0x10
+    field public static final int PSI = 113; // 0x71
+    field public static final int RPM = 2; // 0x2
+    field public static final int SECS = 83; // 0x53
+    field public static final int SHOULD_NOT_USE = 0; // 0x0
+    field public static final int US_GALLON = 66; // 0x42
+    field public static final int WATT_HOUR = 96; // 0x60
+    field public static final int YEAR = 89; // 0x59
+  }
+
 }
 
 package android.car.cluster {
diff --git a/car-lib/src/android/car/VehicleUnit.java b/car-lib/src/android/car/VehicleUnit.java
index 463d53b..4fb099a 100644
--- a/car-lib/src/android/car/VehicleUnit.java
+++ b/car-lib/src/android/car/VehicleUnit.java
@@ -16,6 +16,7 @@
 package android.car;
 
 import android.annotation.IntDef;
+import android.annotation.SystemApi;
 
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
@@ -24,40 +25,52 @@
  * Units used for int or float type with no attached enum types.
  * @hide
  */
+@SystemApi
 public final class VehicleUnit {
     /**
      * List of Unit Types from VHAL
      */
     public static final int SHOULD_NOT_USE = 0x000;
 
-    public static final int METER_PER_SEC = 0x01;
     public static final int RPM = 0x02;
+
     public static final int HERTZ = 0x03;
+
     public static final int PERCENTILE = 0x10;
+
     public static final int MILLIMETER = 0x20;
     public static final int METER = 0x21;
     public static final int KILOMETER = 0x23;
     public static final int MILE = 0x24;
+
+    public static final int METER_PER_SEC = 0x01;
+
     public static final int CELSIUS = 0x30;
     public static final int FAHRENHEIT = 0x31;
     public static final int KELVIN = 0x32;
+
     public static final int MILLILITER = 0x40;
     public static final int LITER = 0x41;
     public static final int US_GALLON  = 0x42;
     public static final int IMPERIAL_GALLON = 0x43;
+
     public static final int NANO_SECS = 0x50;
     public static final int SECS = 0x53;
     public static final int YEAR = 0x59;
-    public static final int KILOPASCAL = 0x70;
-    public static final int WATT_HOUR = 0x60;
+
     public static final int MILLIAMPERE = 0x61;
     public static final int MILLIVOLT = 0x62;
     public static final int MILLIWATTS = 0x63;
+    public static final int WATT_HOUR = 0x60;
     public static final int AMPERE_HOURS = 0x64;
     public static final int KILOWATT_HOUR = 0x65;
+
+    public static final int KILOPASCAL = 0x70;
     public static final int PSI = 0x71;
     public static final int BAR = 0x72;
+
     public static final int DEGREES = 0x80;
+
     /** @hide */
     @Retention(RetentionPolicy.SOURCE)
     @IntDef({