Remove ImageViewTest#testOnSetAlpha

Bug 6293042

Change-Id: I97c41cf1f27838b0fbce3930caf1f7cc59d038a0
diff --git a/tests/tests/widget/src/android/widget/cts/ImageViewTest.java b/tests/tests/widget/src/android/widget/cts/ImageViewTest.java
index 15a4fe7..a213f05 100644
--- a/tests/tests/widget/src/android/widget/cts/ImageViewTest.java
+++ b/tests/tests/widget/src/android/widget/cts/ImageViewTest.java
@@ -410,14 +410,6 @@
         assertTrue(mImageView.getMeasuredHeight() <= 150);
     }
 
-    public void testOnSetAlpha() {
-        MockImageView mockImageView = new MockImageView(mActivity);
-        assertTrue(mockImageView.onSetAlpha(0));
-        MockDrawable drawable = new MockDrawable();
-        mockImageView.setBackgroundDrawable(drawable);
-        assertFalse(mockImageView.onSetAlpha(0));
-    }
-
     public void testSetFrame() {
         MockImageView mockImageView = new MockImageView(mActivity);
         assertFalse(mockImageView.hasOnSizeChangedCalled());