Fix IntDef's usages in the platform Transitions

Bug: 68490704

1) Add annotation in some places where it was missed: constructors of Fade and Slide
2) Add Fade.IN and Fade.OUT into a set of allowed values for Visibility.MODE IntDef. Without it Lint will false alarm on this line:
new Fade().setMode(Fade.IN);
It should be allowed as Fade.IN is just a proxy value for Visibility.MODE_IN.

Test: n/a
Change-Id: I56d8ba5f49b1cf8f6a61357f58ac76312e7cf037

core/java/android/transition/Fade.java

@@ -94,7 +94,7 @@ public class Fade extends Visibility {
      * @param fadingMode The behavior of this transition, a combination of
      * {@link #IN} and {@link #OUT}.
      */
-    public Fade(int fadingMode) {
+    public Fade(@VisibilityMode int fadingMode) {
         setMode(fadingMode);
     }
 

core/java/android/transition/Slide.java

@@ -147,7 +147,7 @@ public class Slide extends Visibility {
     /**
      * Constructor using the provided slide edge direction.
      */
-    public Slide(int slideEdge) {
+    public Slide(@GravityFlag int slideEdge) {
         setSlideEdge(slideEdge);
     }
 

core/java/android/transition/Visibility.java

@@ -52,9 +52,11 @@ public abstract class Visibility extends Transition {
 
     /** @hide */
     @Retention(RetentionPolicy.SOURCE)
-    @IntDef(flag = true, prefix = { "MODE_" }, value = {
+    @IntDef(flag = true, value = {
             MODE_IN,
-            MODE_OUT
+            MODE_OUT,
+            Fade.IN,
+            Fade.OUT
     })
     @interface VisibilityMode {}