chore: remove performance polyfill

shim.js

@@ -204,108 +204,3 @@ if (!console["time"] || !console["timeEnd"]) {
 	};
 }
 
-/**
- * User Timing polyfill (http://www.w3.org/TR/user-timing/)
- * @author RubaXa <trash@rubaxa.org>
- */
-(function (scope) {
-	var
-		startOffset = Date.now ? Date.now() : +(new Date)
-		, performance = scope.performance || {}
-
-		, _entries = []
-		, _marksIndex = {}
-
-		, _filterEntries = function (key, value) {
-			var i = 0, n = _entries.length, result = [];
-			for (; i < n; i++) {
-				if (_entries[i][key] == value) {
-					result.push(_entries[i]);
-				}
-			}
-			return result;
-		}
-
-		, _clearEntries = function (type, name) {
-			var i = _entries.length, entry;
-			while (i--) {
-				entry = _entries[i];
-				if (entry.entryType == type && (name === void 0 || entry.name == name)) {
-					_entries.splice(i, 1);
-				}
-			}
-		}
-		;
-
-
-	if (!performance.now) {
-		performance.now = performance.webkitNow || performance.mozNow || performance.msNow || function () {
-			return (Date.now ? Date.now() : +(new Date)) - startOffset;
-		};
-	}
-
-
-	if (!performance.mark) {
-		performance.mark = performance.webkitMark || function (name) {
-			var mark = {
-				name: name
-				, entryType: 'mark'
-				, startTime: performance.now()
-				, duration: 0
-			};
-			_entries.push(mark);
-			_marksIndex[name] = mark;
-		};
-	}
-
-
-	if (!performance.measure) {
-		performance.measure = performance.webkitMeasure || function (name, startMark, endMark) {
-			startMark = _marksIndex[startMark].startTime;
-			endMark = _marksIndex[endMark].startTime;
-
-			_entries.push({
-				name: name
-				, entryType: 'measure'
-				, startTime: startMark
-				, duration: endMark - startMark
-			});
-		};
-	}
-
-
-	if (!performance.getEntriesByType) {
-		performance.getEntriesByType = performance.webkitGetEntriesByType || function (type) {
-			return _filterEntries('entryType', type);
-		};
-	}
-
-
-	if (!performance.getEntriesByName) {
-		performance.getEntriesByName = performance.webkitGetEntriesByName || function (name) {
-			return _filterEntries('name', name);
-		};
-	}
-
-
-	if (!performance.clearMarks) {
-		performance.clearMarks = performance.webkitClearMarks || function (name) {
-			_clearEntries('mark', name);
-		};
-	}
-
-
-	if (!performance.clearMeasures) {
-		performance.clearMeasures = performance.webkitClearMeasures || function (name) {
-			_clearEntries('measure', name);
-		};
-	}
-
-
-	// exports
-	scope.performance = performance;
-
-	if (typeof define === 'function' && (define.amd || define.ajs)) {
-		define('performance', [], function () { return performance });
-	}
-})(global);