Delete Clock/FakeClock from V2 until we need them.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=119655941

library/src/androidTest/java/com/google/android/exoplayer/testutil/FakeClock.java

-/*
- * Copyright (C) 2014 The Android Open Source Project
- *
- * 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.
- */
-package com.google.android.exoplayer.testutil;
-
-import com.google.android.exoplayer.util.Clock;
-
-/**
- * A {@link Clock} that returns a fixed value specified in the constructor.
- */
-public class FakeClock implements Clock {
-
-  private final long timeMs;
-
-  public FakeClock(long timeMs) {
-    this.timeMs = timeMs;
-  }
-
-  @Override
-  public long elapsedRealtime() {
-    return timeMs;
-  }
-
-}

library/src/main/java/com/google/android/exoplayer/util/Clock.java

-/*
- * Copyright (C) 2014 The Android Open Source Project
- *
- * 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.
- */
-package com.google.android.exoplayer.util;
-
-import android.os.SystemClock;
-
-/**
- * An interface through which system clocks can be read. The {@link SystemClock} implementation
- * must be used for all non-test cases.
- */
-public interface Clock {
-
-  /**
-   * Returns {@link SystemClock#elapsedRealtime}.
-   *
-   * @return Elapsed milliseconds since boot.
-   */
-  long elapsedRealtime();
-
-}