repaint for every change when using formulas in color scales

Change-Id: I1eb42ac75228dee00079c86e7c378efb72f16e28

sc/inc/colorscale.hxx

@@ -59,6 +59,7 @@ public:
     bool GetMin() const;
     bool GetMax() const;
     bool GetPercent() const;
+    bool HasFormula() const;
     void SetMin(bool bMin);
     void SetMax(bool bMax);
     void SetPercent(bool bPercent);

sc/source/core/data/colorscale.cxx

@@ -104,6 +104,11 @@ bool ScColorScaleEntry::GetPercent() const
     return mbPercent;
 }
 
+bool ScColorScaleEntry::HasFormula() const
+{
+    return mpCell;
+}
+
 void ScColorScaleEntry::SetMin(bool bMin)
 {
     mbMin = bMin;
@@ -369,7 +374,13 @@ bool ScColorScaleFormat::CheckEntriesForRel(const ScRange& rRange) const
     for(const_iterator itr = begin(); itr != end(); ++itr)
     {
         if(itr->GetMin() || itr->GetMax())
+        {
             bNeedUpdate = true;
+            break;
+        }
+
+        if(itr->HasFormula())
+            return true;
     }
 
     // TODO: check also if the changed value is the new min/max