Use safe icon when building unavailable slices.

And move ic_a11y_generic from mipmap to drawable. IconCompat doesn't
support mipmap.

Bug: 118691898
Test: robotests
Change-Id: I6799f3d31d2c5654319e5a97bf8ca14992e785a7

src/com/android/settings/slices/SliceBuilderUtils.java

@@ -385,7 +385,7 @@ public class SliceBuilderUtils {
         final Set<String> keywords = buildSliceKeywords(data);
         @ColorInt final int color = Utils.getColorAccentDefaultColor(context);
         final CharSequence summary = context.getText(R.string.disabled_dependent_setting_summary);
-        final IconCompat icon = IconCompat.createWithResource(context, data.getIconResource());
+        final IconCompat icon = getSafeIcon(context, data);
         final SliceAction primaryAction = new SliceAction(getContentPendingIntent(context, data),
                 icon, title);