Make QmlDebug protocol more robust

The protocol so far was client->server only. That is, there was no
sane way for a client to check whether a plugin on the server (service)
was available or not. E.g. calling Client::setEnabled(true) 'succeeded',
without a check whether there is actually a service to talk to.

The new protocol replaces this shortcoming by a service discovery
mechanism: Both client & service announce their available plugins at
handshake time, and later on if there are changes. The status is
reflected in Client::status() and Service::Status() , which are either

  NotConnected - no network connection, or not registered properly
  Unavailable - TCP/IP connection works, but no plugin with the same
name on the other side
  Enabled - You can connect to plugin on other side

The status changes happen automatically (no setEnabled() anymore).

Furthermore a version ID was added to the handshake, so that we can
extend the protocol further in the future :)

1 files changed, 4 insertions, 1 deletions

diff --git a/tests/auto/declarative/qdeclarativedebug/tst_qdeclarativedebug.cpp b/tests/auto/declarative/qdeclarativedebug/tst_qdeclarativedebug.cpp
index adba190..dd58baf 100644
--- a/tests/auto/declarative/qdeclarativedebug/tst_qdeclarativedebug.cpp
+++ b/tests/auto/declarative/qdeclarativedebug/tst_qdeclarativedebug.cpp
@@ -324,13 +324,16 @@ void tst_QDeclarativeDebug::initTestCase()
     bool ok = m_conn->waitForConnected();
     Q_ASSERT(ok);
     QTRY_VERIFY(QDeclarativeDebugService::hasDebuggingClient());
-
     m_dbg = new QDeclarativeEngineDebug(m_conn, this);
+    QTRY_VERIFY(m_dbg->status() == QDeclarativeEngineDebug::Enabled);
 }
 
 void tst_QDeclarativeDebug::cleanupTestCase()
 {
+    delete m_dbg;
+    delete m_conn;
     qDeleteAll(m_components);
+    delete m_engine;
 }
 
 void tst_QDeclarativeDebug::setMethodBody()