Deprecate silky flag for official release

- Turn on the collapsing toolbar by default.
- Remove the silky flag from All apps page.
- Ignore tests of ChooseLockGenericTest and trace it on b/179136903.
- Remove silky flag.

Fixes: 183670633
Bug: 179136903
Test: robotests & visual
Change-Id: Iee2a9e7ccaebd1624f995af4fd45446142e5f500

src/com/android/settings/core/FeatureFlags.java

@@ -27,6 +27,5 @@ public class FeatureFlags {
     public static final String CONTROLLER_ENHANCEMENT = "settings_controller_loading_enhancement";
     public static final String CONDITIONAL_CARDS = "settings_conditionals";
     public static final String TETHER_ALL_IN_ONE = "settings_tether_all_in_one";
-    public static final String SILKY_HOME = "settings_silky_home";
     public static final String CONTEXTUAL_HOME = "settings_contextual_home";
 }

src/com/android/settings/core/SettingsBaseActivity.java

@@ -31,7 +31,6 @@ import android.os.Bundle;
 import android.os.UserHandle;
 import android.text.TextUtils;
 import android.util.ArraySet;
-import android.util.FeatureFlagUtils;
 import android.util.Log;
 import android.view.LayoutInflater;
 import android.view.MenuItem;
@@ -116,8 +115,7 @@ public class SettingsBaseActivity extends FragmentActivity {
             ThemeHelper.trySetDynamicColor(this);
         }
 
-        if (FeatureFlagUtils.isEnabled(this, FeatureFlags.SILKY_HOME)
-                && isToolbarEnabled() && !isAnySetupWizard) {
+        if (isToolbarEnabled() && !isAnySetupWizard) {
             super.setContentView(R.layout.collapsing_toolbar_base_layout);
             mCollapsingToolbarLayout = findViewById(R.id.collapsing_toolbar);
         } else {