Update CachingWidgetPreviewLoaderTest members to be non-static. These classes are stubbed by roboelectric so they cannot be static

Bug: 183335046
Change-Id: Iafb52f87e8e3ece399f4e83c056b2a0dac160d6c
diff --git a/robolectric_tests/src/com/android/launcher3/widget/CachingWidgetPreviewLoaderTest.java b/robolectric_tests/src/com/android/launcher3/widget/CachingWidgetPreviewLoaderTest.java
index c18e26c..1090d1e 100644
--- a/robolectric_tests/src/com/android/launcher3/widget/CachingWidgetPreviewLoaderTest.java
+++ b/robolectric_tests/src/com/android/launcher3/widget/CachingWidgetPreviewLoaderTest.java
@@ -52,15 +52,15 @@
 
 @RunWith(RobolectricTestRunner.class)
 public class CachingWidgetPreviewLoaderTest {
-    private static final Size SIZE_10_10 = new Size(10, 10);
-    private static final Size SIZE_20_20 = new Size(20, 20);
+    private final Size SIZE_10_10 = new Size(10, 10);
+    private final Size SIZE_20_20 = new Size(20, 20);
     private static final String TEST_PACKAGE = "com.example.test";
-    private static final ComponentName TEST_PROVIDER =
+    private final ComponentName TEST_PROVIDER =
             new ComponentName(TEST_PACKAGE, ".WidgetProvider");
-    private static final ComponentName TEST_PROVIDER2 =
+    private final ComponentName TEST_PROVIDER2 =
             new ComponentName(TEST_PACKAGE, ".WidgetProvider2");
-    private static final Bitmap BITMAP = Bitmap.createBitmap(10, 10, Bitmap.Config.ARGB_8888);
-    private static final Bitmap BITMAP2 = Bitmap.createBitmap(20, 20, Bitmap.Config.ARGB_8888);
+    private final Bitmap BITMAP = Bitmap.createBitmap(10, 10, Bitmap.Config.ARGB_8888);
+    private final Bitmap BITMAP2 = Bitmap.createBitmap(20, 20, Bitmap.Config.ARGB_8888);
 
 
     @Mock private CancellationSignal mCancellationSignal;