PLT-4430 improve slow channel switching (#4331)

* PLT-4430 improve slow channel switching

* Update client side unit tests

* Convert getChannelsUnread to getMyChannelMembers and address other feedback

* Pull channel members on websocket reconnect

webapp/tests/client_channel.test.jsx

@@ -232,7 +232,7 @@ describe('Client.Channels', function() {
         TestHelper.initBasic(() => {
             TestHelper.basicClient().getChannels(
                 function(data) {
-                    assert.equal(data.channels.length, 3);
+                    assert.equal(data.length, 3);
                     done();
                 },
                 function(err) {
@@ -261,7 +261,7 @@ describe('Client.Channels', function() {
         TestHelper.initBasic(() => {
             TestHelper.basicClient().getMoreChannels(
                 function(data) {
-                    assert.equal(data.channels.length, 0);
+                    assert.equal(data.length, 0);
                     done();
                 },
                 function(err) {
@@ -285,6 +285,20 @@ describe('Client.Channels', function() {
         });
     });
 
+    it('getMyChannelMembers', function(done) {
+        TestHelper.initBasic(() => {
+            TestHelper.basicClient().getMyChannelMembers(
+                function(data) {
+                    assert.equal(data.length > 0, true);
+                    done();
+                },
+                function(err) {
+                    done(new Error(err.message));
+                }
+            );
+        });
+    });
+
     it('getChannelStats', function(done) {
         TestHelper.initBasic(() => {
             TestHelper.basicClient().getChannelStats(