CredentialsProvider (credentials/credentials_provider.h)

Abstract base class for managing Firebase authentication tokens and user credential changes.

// Source: https://github.com/firebase/firebase-ios-sdk | License: Apache-2.0 | Copyright You must retain, in the Source form of any Derivative Works
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/*
 * Copyright 2018 Google
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License

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