Update icon tint color when the user toggles Dark theme

- Reload theme in slice provider when Dark theme mode changes for slices
- Reload theme in onCreate of Panel activity for its non-slice header
- Remove applyTheme from individual slices

Test: robotest
Fixes: 153700819
Change-Id: I40a7d2817c4b9100d7b2f2962a69c8a9ce6f7906

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

@@ -140,8 +140,11 @@ public class SettingsSliceProvider extends SliceProvider {
     @VisibleForTesting
     Map<Uri, SliceData> mSliceWeakDataCache;
 
+    @VisibleForTesting
     final Map<Uri, SliceBackgroundWorker> mPinnedWorkers = new ArrayMap<>();
 
+    private boolean mNightMode;
+
     public SettingsSliceProvider() {
         super(READ_SEARCH_INDEXABLES);
     }
@@ -150,6 +153,8 @@ public class SettingsSliceProvider extends SliceProvider {
     public boolean onCreateSliceProvider() {
         mSlicesDatabaseAccessor = new SlicesDatabaseAccessor(getContext());
         mSliceWeakDataCache = new WeakHashMap<>();
+        mNightMode = Utils.isNightMode(getContext());
+        getContext().setTheme(R.style.Theme_SettingsBase);
         return true;
     }
 
@@ -201,6 +206,13 @@ public class SettingsSliceProvider extends SliceProvider {
                 return null;
             }
 
+            final boolean nightMode = Utils.isNightMode(getContext());
+            if (mNightMode != nightMode) {
+                Log.d(TAG, "Night mode changed, reload theme");
+                mNightMode = nightMode;
+                getContext().getTheme().rebase();
+            }
+
             // Before adding a slice to {@link CustomSliceManager}, please get approval
             // from the Settings team.
             if (CustomSliceRegistry.isValidUri(sliceUri)) {