Fix a memory leak caused by dashboard freature provider.

In constructor, use app context instead of fragment context

Change-Id: I24fbc457037c1d6854ecf0cb270110d73effb662
Fix: 35292764
Test: RunSettingsRoboTests

src/com/android/settings/dashboard/DashboardFeatureProviderImpl.java

@@ -51,13 +51,13 @@ public class DashboardFeatureProviderImpl implements DashboardFeatureProvider {
     private final CategoryManager mCategoryManager;
 
     public DashboardFeatureProviderImpl(Context context) {
-        mContext = context;
+        mContext = context.getApplicationContext();
         mCategoryManager = CategoryManager.get(context, getExtraIntentAction());
     }
 
     @VisibleForTesting
     DashboardFeatureProviderImpl(Context context, CategoryManager categoryManager) {
-        mContext = context;
+        mContext = context.getApplicationContext();
         mCategoryManager = categoryManager;
     }