consolidate: use KeychainProvider for deletion operation

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/KeychainApplication.java

@@ -103,8 +103,6 @@ public class KeychainApplication extends Application {
         }
     }
 
-
-
     public static void setupAccountAsNeeded(Context context) {
         AccountManager manager = AccountManager.get(context);
         Account[] accounts = manager.getAccountsByType(Constants.PACKAGE_NAME);

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/provider/KeychainDatabase.java

@@ -349,7 +349,7 @@ public class KeychainDatabase extends SQLiteOpenHelper {
         copy(in, out);
     }
 
-    // DANGEROUS
+    // DANGEROUS, use in test code ONLY!
     public void clearDatabase() {
         getWritableDatabase().execSQL("delete from " + Tables.KEY_RINGS_PUBLIC);
     }

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/provider/KeychainProvider.java

@@ -685,6 +685,11 @@ public class KeychainProvider extends ContentProvider {
         final int match = mUriMatcher.match(uri);
 
         switch (match) {
+            // dangerous
+            case KEY_RINGS_UNIFIED: {
+                count = db.delete(Tables.KEY_RINGS_PUBLIC, null, null);
+                break;
+            }
             case KEY_RING_PUBLIC: {
                 @SuppressWarnings("ConstantConditions") // ensured by uriMatcher above
                 String selection = KeyRings.MASTER_KEY_ID + " = " + uri.getPathSegments().get(1);

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/provider/ProviderHelper.java

@@ -963,7 +963,6 @@ public class ProviderHelper {
 
     private ConsolidateResult consolidateDatabaseStep2(Progressable progress, boolean recovery) {
 
-
         Preferences prefs = Preferences.getPreferences(mContext);
 
         // Set flag that we have a cached consolidation here
@@ -986,7 +985,7 @@ public class ProviderHelper {
 
         // 2. wipe database (IT'S DANGEROUS)
         log(LogLevel.DEBUG, LogType.MSG_CON_DB_CLEAR);
-        new KeychainDatabase(mContext).clearDatabase();
+        mContentResolver.delete(KeyRings.buildUnifiedKeyRingsUri(), null, null);
 
         FileImportCache<ParcelableKeyRing> cacheSecret =
                 new FileImportCache<ParcelableKeyRing>(mContext, "consolidate_secret.pcl");