Add description for debugging a remote Gerrit server

Change-Id: I46cbeea6ac768c16ea629c46ae5f40c08b2e9e1d

Documentation/dev-intellij.txt

@@ -151,6 +151,11 @@ The copied run configurations will be added automatically to the available run
 configurations of the IntelliJ project.
 
 ==== Gerrit Daemon
+WARNING: At the moment running this configuration results in a
+`java.io.FileNotFoundException`. To debug a local Gerrit server with IntelliJ,
+use the instructions of <<dev-readme#run_daemon,Running the Daemon>> in
+combination with <<remote-debug,Debugging a remote Gerrit server>>.
+
 Copy `$(gerrit_source_code)/tools/intellij/gerrit_daemon.xml` to
 `$(project_data_directory)/.idea/runConfigurations/`.
 
@@ -173,6 +178,17 @@ TIP: If you would like to execute a test in NoteDb mode, add
 `--test_env=GERRIT_NOTEDB=READ_WRITE` to the *Bazel flags* of your run
 configuration.
 
+[[remote-debug]]
+=== Debugging a remote Gerrit server
+If a remote Gerrit server is running and has opened a debug port, you can attach
+IntelliJ via a `Remote debug configuration`.
+
+. Go to *Run -> Edit Configurations*.
+. Click on the *+* to add a new configuration.
+. Choose *Remote*.
+. Adjust *Configuration -> Settings -> Host* and *Port*.
+. Start this configuration in `Debug` mode.
+
 GERRIT
 ------
 Part of link:index.html[Gerrit Code Review]

Documentation/dev-readme.txt

@@ -159,6 +159,16 @@ copying to the test site:
 NOTE: Please refer to <<special_bazel_java_version,this explanation>>
 for details why using `java -jar` isn't sufficient.
 
+If you want to debug the Gerrit server of this test site, you can open a debug
+port (for example port 5005) by inserting
+
+----
+-agentlib:jdwp=transport=dt_socket,server=y,suspend=n,address=5005
+----
+
+directly after `-jar` of the previous command. Please refer to
+<<dev-intellij#remote-debug,Debugging a remote Gerrit server>> for instructions
+of how to attach IntelliJ.
 
 === Running the Daemon with Gerrit Inspector