CppEditor: Tests: Remove superfluous reference to CppEditorSupport

Also remove the introduced functions in CppEditorSupport. We can just
wait until the document is "Full Checked" via Document::checkmode().

Change-Id: I31d23016f5aa5d3c37e8e05078436ab901bfb2d7
Reviewed-by: Erik Verbruggen <erik.verbruggen@digia.com>

src/plugins/cpptools/cpptoolseditorsupport.h

@@ -95,9 +95,6 @@ public:
     QString contents() const;
     unsigned editorRevision() const;
 
-    bool isDocumentBeingUpdated() const;
-    bool isDocumentScheduledForUpdate() const;
-
     void setExtraDiagnostics(const QString &key,
                              const QList<CPlusPlus::Document::DiagnosticMessage> &messages);