Clean up warnings

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

app/src/main/java/com/wireguard/android/QuickTileService.java

@@ -45,6 +45,7 @@ public class QuickTileService extends TileService {
     private Icon iconOn;
     private Icon iconOff;
 
+    @SuppressWarnings("deprecation")
     @Override
     public void onCreate() {
         final SlashDrawable icon = new SlashDrawable(getResources().getDrawable(R.drawable.ic_tile));

app/src/main/java/com/wireguard/android/widget/SlashDrawable.java

@@ -117,6 +117,7 @@ public class SlashDrawable extends Drawable {
         }
     };
 
+    @SuppressWarnings("unchecked")
     public void setSlashed(final boolean slashed) {
         if (mSlashed == slashed) return;
 
@@ -136,6 +137,7 @@ public class SlashDrawable extends Drawable {
         }
     }
 
+    @SuppressWarnings("deprecation")
     @Override
     public void draw(@NonNull final Canvas canvas) {
         canvas.save();

app/src/main/java/com/wireguard/android/widget/fab/FloatingActionsMenu.java

@@ -35,7 +35,6 @@ import android.widget.TextView;
 
 import com.wireguard.android.R;
 
-@SuppressWarnings("ReturnOfInnerClass")
 public class FloatingActionsMenu extends ViewGroup {
     public static final int EXPAND_UP = 0;
     public static final int EXPAND_DOWN = 1;