QmlProfiler: Remove use of Qt private headers

Use the copy of QDeclarativeDebugClient we ship with qtcreator.
However, since the internal one misses a waitForConnected any connection
will right now fail.

src/plugins/qmlprofiler/tracewindow.cpp

@@ -56,6 +56,8 @@
 
 #define GAP_TIME 150
 
+using QmlJsDebugClient::QDeclarativeDebugClient;
+
 namespace QmlProfiler {
 namespace Internal {