Fix Settings crash when clicking search bar

- When user disable settings suggestion in App Settings, click
search button without leaving settings app. The search button is
still existed.
- Doesn't allow user to disable app in App Settings
- Add check before start search intent

Change-Id: Ifbc4615914678d8df734e14d63bb626403313d1e
Fixes: 118805907
Test: manual

src/com/android/settings/applications/ApplicationFeatureProviderImpl.java

@@ -32,6 +32,7 @@ import android.text.TextUtils;
 import android.util.ArraySet;
 
 import com.android.internal.telephony.SmsApplication;
+import com.android.settings.R;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -138,6 +139,9 @@ public class ApplicationFeatureProviderImpl implements ApplicationFeatureProvide
         if (defaultSms != null) {
             keepEnabledPackages.add(defaultSms.getPackageName());
         }
+        // Keep Settings intelligence enabled, otherwise search feature will be disabled.
+        keepEnabledPackages.add(
+                mContext.getString(R.string.config_settingsintelligence_package_name));
         return keepEnabledPackages;
     }