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@pmwcs/base

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"use strict"; Object.defineProperty(exports, "__esModule", { value: true }); exports.applyPassive = applyPassive; /** * @license * Copyright 2019 Google Inc. * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. */ /** * Stores result from applyPassive to avoid redundant processing to detect * passive event listener support. */ var supportsPassive_; /** * Determine whether the current browser supports passive event listeners, and * if so, use them. */ function applyPassive(globalObj, forceRefresh) { if (globalObj === undefined) { globalObj = window; } if (forceRefresh === undefined) { forceRefresh = false; } if (supportsPassive_ === undefined || forceRefresh) { var isSupported = false; try { globalObj.document.addEventListener('test', function () { return undefined; }, { get passive() { isSupported = true; return isSupported; } }); } catch (e) {} supportsPassive_ = isSupported; } return supportsPassive_ ? { passive: true } : false; }