Remove references to 'robolectric.nativeruntime.enableGraphics'

This system property was only used during the development of
Robolectric Native Graphics (RNG). Now that RNG code has been
merged upstream to GitHub, the graphics mode can be checked
directly.

PiperOrigin-RevId: 504464649

library/test/src/test/java/com/bumptech/glide/load/resource/bitmap/TransformationUtilsTest.java

@@ -358,7 +358,7 @@ public void testRotateImage() {
 
     Bitmap ninety = TransformationUtils.rotateImage(toRotate, 90);
     // Checks if native graphics is enabled.
-    if (Boolean.getBoolean("robolectric.nativeruntime.enableGraphics")) {
+    if (System.getProperty("robolectric.graphicsMode", "").equals("NATIVE")) {
       assertThat(ninety.getPixel(0, 0)).isEqualTo(Color.RED);
       assertThat(ninety.getPixel(1, 0)).isEqualTo(Color.BLUE);
     } else {