Update the makesteps the summary on build directory changes

Also ensure that Qt4ProjectConfigWidget does not emit any signals from
it's init method.

src/plugins/qt4projectmanager/qt4project.cpp

@@ -1004,7 +1004,7 @@ void Qt4Project::updateActiveRunConfiguration()
         }
     }
     emit runConfigurationsEnabledStateChanged();
-    emit invalidateCachedTargetInformation();
+    emit targetInformationChanged();
 }
 
 ProjectExplorer::ToolChain::ToolChainType Qt4Project::toolChainType(BuildConfiguration *configuration) const
@@ -1207,6 +1207,11 @@ void Qt4Project::invalidateCachedTargetInformation()
     emit targetInformationChanged();
 }
 
+void Qt4Project::emitBuildDirectoryChanged()
+{
+    emit buildDirectoryChanged();
+}
+
 // We match -spec and -platfrom separetly
 // We ignore -cache, because qmake contained a bug that it didn't
 // mention the -cache in the Makefile