Support highlightable Settings homepage menu for 2-pane

1. Add a preference group adapter to perform highlighting
2. Add a class for mapping highlighable menu keys and preference keys
3. Add an API to determine if the screen is in split mode

Bug: 199017944
Test: manual, build
Change-Id: I8e3fe5fb96480a31ee0f3b3afb6ad78999d3d2bc

src/com/android/settings/activityembedding/ActivityEmbeddingUtils.java

@@ -62,4 +62,12 @@ public class ActivityEmbeddingUtils {
 
         return isFlagEnabled && isSplitSupported;
     }
+
+    /** Whether the screen meets two-pane resolution. */
+    public static boolean isTwoPaneResolution(Context context) {
+        final Context appContext = context.getApplicationContext();
+        final DisplayMetrics dm = appContext.getResources().getDisplayMetrics();
+        return dm.widthPixels >= getMinCurrentScreenSplitWidthPx(appContext)
+                && dm.heightPixels >= getMinSmallestScreenSplitWidthPx(appContext);
+    }
 }