Revert of Revert of ServiceWorker: Remove Clients.getAll()

LayoutTests/http/tests/serviceworker/chromium/resources/windowclient-focus.js

 // This helper will setup a small test framework that will use TESTS and run
 // them sequentially and call self.postMessage('quit') when done.
 // This helper also exposes |client|, |postMessage()|, |runNextTestOrQuit()|,
 // |synthesizeNotificationClick()| and |initialize()|.
 importScripts('sw-test-helpers.js');
 
 // Clients nested inside the main client (|client|) used in this test.
 var nestedClients = [];
 
 // Override self.initialize() from sw-test-helpers.js
 self.initialize = function() {
-    return self.clients.getAll().then(function(clients) {
+    return self.clients.matchAll().then(function(clients) {
         clients.forEach(function(c) {
             // All clients are iframes but one of them embeds the other ones. We
             // want to use that one as the main |client|.
             // Its url ends with '.html' while the others ends with '.html?X'
             if (c.url.endsWith('.html'))
                 client = c;
             else
                 nestedClients.push(c);
         });
     });
 };
 
 function getNumberOfFocusedClients() {
-  return self.clients.getAll().then(function(clients) {
+  return self.clients.matchAll().then(function(clients) {
     var focusedClients = 0;
     clients.forEach(function(c) {
       if (c.focused)
         ++focusedClients;
     });
     return focusedClients;
   });
 }
 
 var TESTS = [
@@ skipping 90 matching lines @@
 self.onmessage = function(e) {
     if (e.data == 'start') {
         initialize().then(runNextTestOrQuit);
     } else {
         initialize().then(function() {
             self.postMessage('received unexpected message');
             self.postMessage('quit');
         });
     }
 };