Remove legacy getStats polyfill

which provides a way to turn legacy stats into a maplike object.
Legacy getStats have since been removed from Chrome.

Fixes webrtcHacks#1137

Author: fippo

index.d.ts

@@ -17,7 +17,6 @@ declare module "webrtc-adapter" {
         shimMediaStream(window: Window): void;
         shimOnTrack(window: Window): void;
         shimGetSendersWithDtmf(window: Window): void;
-        shimGetStats(window: Window): void;
         shimSenderReceiverGetStats(window: Window): void;
         shimAddTrackRemoveTrackWithNative(window: Window): void;
         shimAddTrackRemoveTrack(window: Window): void;

src/js/adapter_factory.js

@@ -60,7 +60,6 @@ export function adapterFactory({window} = {}, options = {
       chromeShim.shimOnTrack(window, browserDetails);
       chromeShim.shimAddTrackRemoveTrack(window, browserDetails);
       chromeShim.shimGetSendersWithDtmf(window, browserDetails);
-      chromeShim.shimGetStats(window, browserDetails);
       chromeShim.shimSenderReceiverGetStats(window, browserDetails);
       chromeShim.fixNegotiationNeeded(window, browserDetails);
 

src/js/chrome/chrome_shim.js

@@ -188,73 +188,6 @@ export function shimGetSendersWithDtmf(window) {
   }
 }
 
-export function shimGetStats(window) {
-  if (!window.RTCPeerConnection) {
-    return;
-  }
-
-  const origGetStats = window.RTCPeerConnection.prototype.getStats;
-  window.RTCPeerConnection.prototype.getStats = function getStats() {
-    const [selector, onSucc, onErr] = arguments;
-
-    // If selector is a function then we are in the old style stats so just
-    // pass back the original getStats format to avoid breaking old users.
-    if (arguments.length > 0 && typeof selector === 'function') {
-      return origGetStats.apply(this, arguments);
-    }
-
-    // When spec-style getStats is supported, return those when called with
-    // either no arguments or the selector argument is null.
-    if (origGetStats.length === 0 && (arguments.length === 0 ||
-        typeof selector !== 'function')) {
-      return origGetStats.apply(this, []);
-    }
-
-    const fixChromeStats_ = function(response) {
-      const standardReport = {};
-      const reports = response.result();
-      reports.forEach(report => {
-        const standardStats = {
-          id: report.id,
-          timestamp: report.timestamp,
-          type: {
-            localcandidate: 'local-candidate',
-            remotecandidate: 'remote-candidate'
-          }[report.type] || report.type
-        };
-        report.names().forEach(name => {
-          standardStats[name] = report.stat(name);
-        });
-        standardReport[standardStats.id] = standardStats;
-      });
-
-      return standardReport;
-    };
-
-    // shim getStats with maplike support
-    const makeMapStats = function(stats) {
-      return new Map(Object.keys(stats).map(key => [key, stats[key]]));
-    };
-
-    if (arguments.length >= 2) {
-      const successCallbackWrapper_ = function(response) {
-        onSucc(makeMapStats(fixChromeStats_(response)));
-      };
-
-      return origGetStats.apply(this, [successCallbackWrapper_,
-        selector]);
-    }
-
-    // promise-support
-    return new Promise((resolve, reject) => {
-      origGetStats.apply(this, [
-        function(response) {
-          resolve(makeMapStats(fixChromeStats_(response)));
-        }, reject]);
-    }).then(onSucc, onErr);
-  };
-}
-
 export function shimSenderReceiverGetStats(window) {
   if (!(typeof window === 'object' && window.RTCPeerConnection &&
       window.RTCRtpSender && window.RTCRtpReceiver)) {