Fix all our unused parameter warnings so we let GCC report them.

There were a couple of genuine bugs here (fixed), plus there's a missing
feature in trace.cc that I've just added a TODO for.

Also note that I haven't touched the compilers; this warning is still
explicitly disabled for that code. I'll do that when there's less going
on in those directories.

Change-Id: Ic3570bf82411a07c7530bfaf1995ac995b9fc00f
diff --git a/src/jdwp/jdwp_adb.cc b/src/jdwp/jdwp_adb.cc
index eb49bce..ae45f18 100644
--- a/src/jdwp/jdwp_adb.cc
+++ b/src/jdwp/jdwp_adb.cc
@@ -294,7 +294,7 @@
 /*
  * Connect out to a debugger (for server=n).  Not required.
  */
-static bool establishConnection(JdwpState* state) {
+static bool establishConnection(JdwpState*) {
   return false;
 }