CppEditor: Move static symbol finder instance to CppTools

...to it can be reused by other clients more easily. Also, in a
follow-up change it will have a project part dependency that can be
cleared inside the CppModelManager more easily.

Change-Id: Ic9f2ce5212a94fd05ab0571e9ad99d0a25f5bc5c
Reviewed-by: Marco Bubke <marco.bubke@theqtcompany.com>

src/plugins/cpptools/cppmodelmanager.cpp

@@ -44,6 +44,7 @@
 #include "cpptoolsplugin.h"
 #include "cpptoolsreuse.h"
 #include "editordocumenthandle.h"
+#include "symbolfinder.h"
 
 #include <coreplugin/documentmanager.h>
 #include <coreplugin/icore.h>
@@ -163,6 +164,8 @@ public:
 
     CppFindReferences *m_findReferences;
 
+    SymbolFinder m_symbolFinder;
+
     bool m_enableGC;
     QTimer m_delayedGcTimer;
 };
@@ -1272,4 +1275,9 @@ void CppModelManager::enableGarbageCollector(bool enable)
     d->m_enableGC = enable;
 }
 
+SymbolFinder *CppModelManager::symbolFinder()
+{
+    return &d->m_symbolFinder;
+}
+
 } // namespace CppTools