Reland of 'Move content/browser/power_save_blocker to //device/power_save_blocker'

content/public/android/java/src/org/chromium/content/browser/PowerSaveBlocker.java

-// Copyright 2013 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-package org.chromium.content.browser;
-
-import android.view.View;
-
-import org.chromium.base.annotations.CalledByNative;
-import org.chromium.base.annotations.JNINamespace;
-import org.chromium.ui.base.ViewAndroidDelegate;
-
-import java.lang.ref.WeakReference;
-
-@JNINamespace("content")
-class PowerSaveBlocker {
-    // WeakReference to prevent leaks in Android WebView.
-    private WeakReference<View> mKeepScreenOnView;
-
-    @CalledByNative
-    private static PowerSaveBlocker create() {
-        return new PowerSaveBlocker();
-    }
-
-    private PowerSaveBlocker() {}
-
-    @CalledByNative
-    private void applyBlock(ViewAndroidDelegate delegate) {
-        assert mKeepScreenOnView == null;
-        View anchorView = delegate.acquireAnchorView();
-        mKeepScreenOnView = new WeakReference<>(anchorView);
-        delegate.setAnchorViewPosition(anchorView, 0, 0, 0, 0);
-        anchorView.setKeepScreenOn(true);
-    }
-
-    @CalledByNative
-    private void removeBlock(ViewAndroidDelegate delegate) {
-        assert mKeepScreenOnView != null;
-        View anchorView = mKeepScreenOnView.get();
-        mKeepScreenOnView = null;
-        if (anchorView == null) return;
-
-        anchorView.setKeepScreenOn(false);
-        delegate.releaseAnchorView(anchorView);
-    }
-}