Enable advanced Java interop tests.

Add response parameters to custom_metadata streaming request for Node and PHP
clients.

The Java server does not respond with separate initial and trailing
metadata when there is no response data - it is only emiting the
requested trailing metadata. Adding the response parameters to the test
(in accordance with the specification) avoids this, but I will open a
separate issue to investigate the Java behavior.
diff --git a/tools/run_tests/run_interop_tests.py b/tools/run_tests/run_interop_tests.py
index c14f18a..981e38b 100755
--- a/tools/run_tests/run_interop_tests.py
+++ b/tools/run_tests/run_interop_tests.py
@@ -179,10 +179,10 @@
     return {}
 
   def unimplemented_test_cases(self):
-    return _SKIP_ADVANCED + _SKIP_COMPRESSION
+    return _SKIP_COMPRESSION
 
   def unimplemented_test_cases_server(self):
-    return _SKIP_ADVANCED + _SKIP_COMPRESSION
+    return _SKIP_COMPRESSION
 
   def __str__(self):
     return 'java'