[RemotePlayback] Implement 'connecting' state

third_party/WebKit/Source/modules/remoteplayback/RemotePlayback.cpp

Index: third_party/WebKit/Source/modules/remoteplayback/RemotePlayback.cpp
diff --git a/third_party/WebKit/Source/modules/remoteplayback/RemotePlayback.cpp b/third_party/WebKit/Source/modules/remoteplayback/RemotePlayback.cpp
index f8f23bc6320c42579794fc092e8dc11f6d53862f..44f8a2dffe919011e88c546111a96e0c8fd856f1 100644
--- a/third_party/WebKit/Source/modules/remoteplayback/RemotePlayback.cpp
+++ b/third_party/WebKit/Source/modules/remoteplayback/RemotePlayback.cpp
@@ -209,23 +209,26 @@ void RemotePlayback::notifyInitialAvailability(int callbackId) {
 }
 
 void RemotePlayback::stateChanged(WebRemotePlaybackState state) {
-  // We may get a "disconnected" state change while in the "disconnected"
-  // state if initiated connection fails. So cleanup the promise resolvers
-  // before checking if anything changed.
-  // TODO(avayvod): cleanup this logic when we implementing the "connecting"
-  // state.
+  if (m_state == state)
+    return;
+
   if (m_promptPromiseResolver) {
-    if (state != WebRemotePlaybackState::Disconnected)
-      m_promptPromiseResolver->resolve();
-    else
+    // If we're trying to connect and failed, reject the promise.
+    // Otherwise, resolve it.
+    if (m_state == WebRemotePlaybackState::Connecting &&
+        state == WebRemotePlaybackState::Disconnected) {
       m_promptPromiseResolver->reject(DOMException::create(
           AbortError, "Failed to connect to the remote device."));
+    } else {
+      DCHECK((m_state == WebRemotePlaybackState::Disconnected &&
+              state == WebRemotePlaybackState::Connecting) ||
+             (m_state == WebRemotePlaybackState::Connected &&
+              state == WebRemotePlaybackState::Disconnected));
+      m_promptPromiseResolver->resolve();
+    }
     m_promptPromiseResolver = nullptr;
   }
 
-  if (m_state == state)
-    return;
-
   m_state = state;
   switch (m_state) {
     case WebRemotePlaybackState::Connecting: