CppTools: Move CppHoverHandler to CppTools

This is in preparation for clang code model to provide its own hover
handler.

Change-Id: Ifbdd96f427989bd5d1fbc4badb9c38108485c2f2
Reviewed-by: Ivan Donchevskii <ivan.donchevskii@qt.io>

src/plugins/cpptools/cppmodelmanagersupport.h

@@ -30,7 +30,10 @@
 #include <QSharedPointer>
 #include <QString>
 
-namespace TextEditor { class TextDocument; }
+namespace TextEditor {
+class TextDocument;
+class BaseHoverHandler;
+} // namespace TextEditor
 
 namespace CppTools {
 
@@ -48,6 +51,7 @@ public:
     virtual ~ModelManagerSupport() = 0;
 
     virtual CppCompletionAssistProvider *completionAssistProvider() = 0;
+    virtual TextEditor::BaseHoverHandler *createHoverHandler() = 0;
     virtual BaseEditorDocumentProcessor *createEditorDocumentProcessor(
                 TextEditor::TextDocument *baseTextDocument) = 0;
     virtual FollowSymbolInterface &followSymbolInterface() = 0;