activemq: Adding plist configured with AbandonProcessGroup=true, ad…

…dressing original issue in #39477.

Closes #2825.

Signed-off-by: Alex Dunn <dunn.alex@gmail.com>

Formula/activemq.rb

@@ -14,6 +14,32 @@ def install
     (bin/"activemq").write_env_script libexec/"bin/activemq", Language::Java.java_home_env("1.6+")
   end
 
+  plist_options :manual => "activemq start"
+
+  def plist; <<-EOS.undent
+    <?xml version="1.0" encoding="UTF-8"?>
+    <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN"
+    "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+    <plist version="1.0">
+      <dict>
+        <key>Label</key>
+        <string>#{plist_name}</string>
+        <key>RunAtLoad</key>
+        <true/>
+        <key>AbandonProcessGroup</key>
+        <true/>
+        <key>WorkingDirectory</key>
+        <string>#{libexec}</string>
+        <key>ProgramArguments</key>
+        <array>
+          <string>#{opt_bin}/activemq</string>
+          <string>start</string>
+        </array>
+      </dict>
+    </plist>
+    EOS
+  end
+
   test do
     system "#{bin}/activemq", "browse", "-h"
   end