Refactor CaptionAppearanceFragment to improve maintainability (4/n)

Root cause: There is a bunch of different logic of preferences in CaptionAppearanceFragment. It’s hard to implement new features and hard to maintain and hard to be testable.
Solution: Move out preset preference logic of CaptionAppearanceFragment into controllers to reduce the complexity of the relationship between preference and fragment.

Bug: 197695932
Test: make RunSettingsRoboTests ROBOTEST_FILTER=CaptionPresetControllerTest CaptionAppearanceFragmentTest
Change-Id: I5409c1e8a6bdfc633abc304d8cf800ea0943de78

src/com/android/settings/accessibility/CaptionHelper.java

@@ -186,4 +186,19 @@ public class CaptionHelper {
         final CaptionStyle attrs = CaptionStyle.getCustomStyle(mContentResolver);
         return attrs.edgeType;
     }
+
+    /**
+     * Sets the caption raw user style.
+     *
+     * @param type The caption raw user style
+     */
+    public void setRawUserStyle(int type) {
+        Settings.Secure.putInt(mContentResolver,
+                Settings.Secure.ACCESSIBILITY_CAPTIONING_PRESET, type);
+    }
+
+    /** Returns the caption raw user style.*/
+    public int getRawUserStyle() {
+        return mCaptioningManager.getRawUserStyle();
+    }
 }