Consume events-broker from source

Also amend the build.md with the explicit mention to the events-broker
as pre-requisite for building the plugin.

Change-Id: I90f27530dc32786443140adf0a543daf4872c2d4
diff --git a/BUILD b/BUILD
index f0fff60..4ea096e 100644
--- a/BUILD
+++ b/BUILD
@@ -11,7 +11,7 @@
     srcs = glob(["src/main/java/**/*.java"]),
     resources = glob(["src/main/resources/**/*"]),
     deps = [
-        "@events-broker//jar",
+        ":events-broker-neverlink",
     ],
     manifest_entries = [
         "Gerrit-PluginName: websession-broker",
@@ -38,6 +38,12 @@
     exports = PLUGIN_DEPS + PLUGIN_TEST_DEPS + [
         ":websession-broker__plugin",
         "@mockito//jar",
-        "@events-broker//jar",
+        "//plugins/events-broker",
     ],
 )
+
+java_library(
+    name = "events-broker-neverlink",
+    neverlink = 1,
+    exports = ["//plugins/events-broker"],
+)
diff --git a/external_plugin_deps.bzl b/external_plugin_deps.bzl
index 967f8dc..1d8851b 100644
--- a/external_plugin_deps.bzl
+++ b/external_plugin_deps.bzl
@@ -15,12 +15,6 @@
     BYTE_BUDDY_VERSION = "1.9.10"
 
     maven_jar(
-        name = "events-broker",
-        artifact = "com.gerritforge:events-broker:3.4.0.4",
-        sha1 = "8d361d863382290e33828116e65698190118d0f1",
-    )
-
-    maven_jar(
         name = "byte-buddy",
         artifact = "net.bytebuddy:byte-buddy:" + BYTE_BUDDY_VERSION,
         sha1 = "211a2b4d3df1eeef2a6cacf78d74a1f725e7a840",
diff --git a/src/main/resources/Documentation/build.md b/src/main/resources/Documentation/build.md
index d18e927..86b1063 100644
--- a/src/main/resources/Documentation/build.md
+++ b/src/main/resources/Documentation/build.md
@@ -6,6 +6,8 @@
 Clone (or link) this plugin to the `plugins` directory of Gerrit's
 source tree. Put the external dependency Bazel build file into
 the Gerrit /plugins directory, replacing the existing empty one.
+The plugin depends on [events-broker](https://gerrit.googlesource.com/modules/events-broker)
+which is linked directly from source with the same 'in-tree' plugin structure.
 
 ```
   cd gerrit/plugins