ProjectExplorer: Add "build for current run config" menu entry

This lets users build the executable corresponding to the currently
active run configuration. It's functionally equivalent to locating the
corresponding node in the project tree and choosing "Build" from the
context menu.

Fixes: QTCREATORBUG-22403
Change-Id: Ic2b729c7ce17f1ad944dc06746bb9d6db90b6c61
Reviewed-by: hjk <hjk@qt.io>

src/plugins/cmakeprojectmanager/cmakeproject.cpp

@@ -87,6 +87,7 @@ CMakeProject::CMakeProject(const FilePath &fileName) : Project(Constants::CMAKEM
     setId(CMakeProjectManager::Constants::CMAKEPROJECT_ID);
     setProjectLanguages(Core::Context(ProjectExplorer::Constants::CXX_LANGUAGE_ID));
     setDisplayName(projectDirectory().fileName());
+    setCanBuildProducts();
 
     // Timer:
     m_delayedParsingTimer.setSingleShot(true);