Load plugins in the same thread, so we know if they failed or not

This way we can update the capabilities accordingly.

src/org/kde/kdeconnect/Device.java

@@ -692,24 +692,20 @@ public class Device implements BaseLink.PackageReceiver {
         return plugin;
     }
 
-    private synchronized void addPlugin(final String pluginKey) {
+    private synchronized boolean addPlugin(final String pluginKey) {
         Plugin existing = plugins.get(pluginKey);
         if (existing != null) {
             //Log.w("KDE/addPlugin","plugin already present:" + pluginKey);
-            return;
+            return false;
         }
 
         final Plugin plugin = PluginFactory.instantiatePluginForDevice(context, pluginKey, this);
         if (plugin == null) {
             Log.e("KDE/addPlugin","could not instantiate plugin: "+pluginKey);
             failedPlugins.put(pluginKey, null);
-            return;
+            return false;
         }
 
-        new Handler(Looper.getMainLooper()).post(new Runnable() {
-            @Override
-            public void run() {
-
         boolean success;
         try {
             success = plugin.onCreate();
@@ -729,9 +725,7 @@ public class Device implements BaseLink.PackageReceiver {
             failedPlugins.put(pluginKey, plugin);
         }
 
-            }
-        });
-
+        return success;
     }
 
     private synchronized boolean removePlugin(String pluginKey) {
@@ -816,8 +810,9 @@ public class Device implements BaseLink.PackageReceiver {
             }
 
             if (pluginEnabled) {
-                addPlugin(pluginKey);
+                boolean success = addPlugin(pluginKey);
 
+                if (success) {
                     for (String packageType : incomingInterfaces) {
                         ArrayList<String> plugins = newPluginsByIncomingInterface.get(packageType);
                         if (plugins == null) plugins = new ArrayList<>();
@@ -830,6 +825,7 @@ public class Device implements BaseLink.PackageReceiver {
                         plugins.add(pluginKey);
                         newPluginsByOutgoingInterface.put(packageType, plugins);
                     }
+                }
             } else {
                 removePlugin(pluginKey);
             }

src/org/kde/kdeconnect/Plugins/ClibpoardPlugin/ClipboardListener.java

@@ -25,6 +25,8 @@ import android.content.ClipData;
 import android.content.Context;
 import android.content.ClipboardManager;
 import android.os.Build;
+import android.os.Handler;
+import android.os.Looper;
 
 import org.kde.kdeconnect.Device;
 import org.kde.kdeconnect.NetworkPackage;
@@ -45,6 +47,9 @@ public class ClipboardListener {
             return;
         }
 
+        new Handler(Looper.getMainLooper()).post(new Runnable() {
+            @Override
+            public void run() {
                 cm = (ClipboardManager) context.getSystemService(Context.CLIPBOARD_SERVICE);
                 listener = new ClipboardManager.OnPrimaryClipChangedListener() {
                     @Override
@@ -68,6 +73,8 @@ public class ClipboardListener {
                 };
                 cm.addPrimaryClipChangedListener(listener);
             }
+        });
+    }
 
     public void stop() {
         if(android.os.Build.VERSION.SDK_INT < 11) {