[RN] Detect errors when loading the configuration

The error is stored in the redux store in base/config so other components can
consult it. It is also broadcasted as a new event in the external API for the
SDK.

android/README.md

@@ -241,3 +241,9 @@ The `data` HashMap contains a "url" key with the conference URL.
 Called before a conference is left.
 
 The `data` HashMap contains a "url" key with the conference URL.
+
+#### onLoadConfigError
+
+Called when loading the main configuration fails.
+
+The `data` HashMap contains a "error" key with the error.

android/sdk/src/main/java/org/jitsi/meet/sdk/JitsiMeetViewAdapter.java

@@ -57,4 +57,11 @@ public abstract class JitsiMeetViewAdapter implements JitsiMeetViewListener {
     @Override
     public void onConferenceWillLeave(Map<String, Object> data) {
     }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public void onLoadConfigError(Map<String, Object> data) {
+    }
 }

android/sdk/src/main/java/org/jitsi/meet/sdk/JitsiMeetViewListener.java

@@ -58,4 +58,11 @@ public interface JitsiMeetViewListener {
      * @param data - Map with a "url" key with the conference URL.
      */
     void onConferenceWillLeave(Map<String, Object> data);
+
+    /**
+     * Called when loading the main configuration fails.
+     *
+     * @param data - Map with a "error" key with the error.
+     */
+    void onLoadConfigError(Map<String, Object> data);
 }