fix CTS test. RGBX_8888 is a 32 bits format

Bug: 10310106
Change-Id: I00de4e95a4cdcbd44010eb3ace926a39f5e2eef8
diff --git a/tests/tests/graphics/src/android/graphics/cts/PixelFormatTest.java b/tests/tests/graphics/src/android/graphics/cts/PixelFormatTest.java
index dcbb084..4809755 100644
--- a/tests/tests/graphics/src/android/graphics/cts/PixelFormatTest.java
+++ b/tests/tests/graphics/src/android/graphics/cts/PixelFormatTest.java
@@ -46,7 +46,7 @@
 
         PixelFormat.getPixelFormatInfo(PixelFormat.RGBX_8888, mPixelFormat);
         assertEquals(4, mPixelFormat.bytesPerPixel);
-        assertEquals(24, mPixelFormat.bitsPerPixel);
+        assertEquals(32, mPixelFormat.bitsPerPixel);
 
         PixelFormat.getPixelFormatInfo(PixelFormat.RGB_888, mPixelFormat);
         assertEquals(3, mPixelFormat.bytesPerPixel);