Fix a missing header path when building with Qt 4.

Also, removing explicit include path configuration,
since QT_USE_FILE takes care of that.

cmake/OpenCVFindLibsGUI.cmake

@@ -33,7 +33,7 @@ if(WITH_QT)
   endif()
 
   if(NOT HAVE_QT)
-    find_package(Qt4)
+    find_package(Qt4 REQUIRED QtCore QtGui QtTest)
     if(QT4_FOUND)
       set(HAVE_QT TRUE)
       add_definitions(-DHAVE_QT) # We need to define the macro this way, using cvconfig.h does not work

modules/highgui/CMakeLists.txt

@@ -95,14 +95,10 @@ elseif(HAVE_QT)
   endif()
   include(${QT_USE_FILE})
 
-  if(QT_INCLUDE_DIR)
-    ocv_include_directories(${QT_INCLUDE_DIR})
-  endif()
-
   QT4_ADD_RESOURCES(_RCC_OUTFILES src/window_QT.qrc)
   QT4_WRAP_CPP(_MOC_OUTFILES src/window_QT.h)
 
-  list(APPEND HIGHGUI_LIBRARIES ${QT_LIBRARIES} ${QT_QTTEST_LIBRARY})
+  list(APPEND HIGHGUI_LIBRARIES ${QT_LIBRARIES})
   list(APPEND highgui_srcs src/window_QT.cpp ${_MOC_OUTFILES} ${_RCC_OUTFILES})
   ocv_check_flag_support(CXX -Wno-missing-declarations _have_flag)
   if(${_have_flag})