removed requestAnimationFrame hook

Former-commit-id: e90d0fcfca305ab06db89030a52e75dac62afa16

lib/single-file/processors/hooks/content/content-hooks-frames-web.js

@@ -53,17 +53,13 @@
 	const UIEvent = window.UIEvent;
 	const FileReader = window.FileReader;
 	const Blob = window.Blob;
-	const requestAnimationFrame = window.requestAnimationFrame;
-	const cancelAnimationFrame = window.cancelAnimationFrame;
 	const console = window.console;
 	const warn = (console && console.warn) || (() => { });
 
 	const observers = new Map();
 	const observedElements = new Map();
-	let loadDeferredImages;
 
 	addEventListener.call(window, LOAD_DEFERRED_IMAGES_START_EVENT, () => {
-		loadDeferredImages = true;
 		const scrollingElement = document.scrollingElement || document.documentElement;
 		const clientHeight = scrollingElement.clientHeight;
 		const clientWidth = scrollingElement.clientWidth;
@@ -154,12 +150,6 @@
 				}), intersectionObserver);
 			}
 		});
-		if (pendingRequestAnimationFrameCalls.size) {
-			[...pendingRequestAnimationFrameCalls].forEach(([id, callback]) => {
-				cancelAnimationFrame(id);
-				callback();
-			});
-		}
 	});
 
 	addEventListener.call(window, LOAD_DEFERRED_IMAGES_END_EVENT, () => {
@@ -181,7 +171,6 @@
 			window.Image = window._singleFileImage;
 			delete window._singleFileImage;
 		}
-		loadDeferredImages = false;
 		dispatchEvent.call(window, new UIEvent("resize"));
 		dispatchEvent.call(window, new UIEvent("scroll"));
 	});
@@ -222,50 +211,6 @@
 		}
 	});
 
-	let warningRequestAnimationFrameDisplayed;
-	const pendingRequestAnimationFrameCalls = new Map();
-	let lastTimestamp = 0;
-	let errorDetected;
-	window.requestAnimationFrame = function (callback) {
-		if (!warningRequestAnimationFrameDisplayed) {
-			warn.call(console, "SingleFile is hooking the requestAnimationFrame and cancelAnimationFrame functions to load deferred images in background tabs."); // eslint-disable-line no-console
-			warningRequestAnimationFrameDisplayed = true;
-		}
-		let requestId;
-		if (loadDeferredImages && !errorDetected) {
-			try {
-				requestId = 0;
-				callback(lastTimestamp);
-			} catch (error) {
-				errorDetected = true;
-				requestId = requestAnimationFrame(timestamp => {
-					lastTimestamp = timestamp;
-					callback(timestamp);
-				});
-			}
-		} else {
-			if (!loadDeferredImages) {
-				errorDetected = false;
-			}
-			requestId = requestAnimationFrame(timestamp => {
-				pendingRequestAnimationFrameCalls.delete(requestId);
-				lastTimestamp = timestamp;
-				callback(timestamp);
-			});
-			if (!loadDeferredImages || pendingRequestAnimationFrameCalls.length < 128) {
-				pendingRequestAnimationFrameCalls.set(requestId, callback);
-			}
-		}
-		return requestId;
-	};
-	window.requestAnimationFrame.toString = function () { return "requestAnimationFrame() { [native code] }"; };
-
-	window.cancelAnimationFrame = function (requestId) {
-		pendingRequestAnimationFrameCalls.delete(requestId);
-		return cancelAnimationFrame(requestId);
-	};
-	window.cancelAnimationFrame.toString = function () { return "cancelAnimationFrame() { [native code] }"; };
-
 	if (window.FontFace) {
 		const FontFace = window.FontFace;
 		let warningFontFaceDisplayed;