The string "###" can be written as such, no need for a Special Const Variable

Change-Id: Ib9737acc8e0a9845fc03ed2c7de7969cef41f27c

chart2/inc/SpecialUnicodes.hxx

@@ -11,7 +11,6 @@
 #define INCLUDED_CHART2_INC_SPECIALUNICODES_HXX
 
 const sal_Unicode aMinusSign = 0x2212;
-const OUString aHashString ("###");
 const sal_Unicode aSuperscriptFigures[10]={ 0x2070, 0x00B9, 0x00B2, 0x00B3, 0x2074, 0x2075, 0x2076, 0x2077, 0x2078, 0x2079 };
 
 #endif

chart2/source/tools/MeanValueRegressionCurveCalculator.cxx

@@ -23,7 +23,6 @@
 #include <osl/diagnose.h>
 #include <rtl/math.hxx>
 #include <rtl/ustrbuf.hxx>
-#include <SpecialUnicodes.hxx>
 
 using namespace ::com::sun::star;
 
@@ -121,7 +120,7 @@ OUString MeanValueRegressionCurveCalculator::ImplGetRepresentation(
     {
         *pFormulaLength -= aBuf.getLength();
         if ( *pFormulaLength <= 0 )
-            return aHashString;
+            return OUString("###");
     }
     return ( aBuf + getFormattedString( xNumFormatter, nNumberFormatKey, m_fMeanValue, pFormulaLength ) );
 }

chart2/source/tools/RegressionCurveCalculator.cxx

@@ -30,8 +30,6 @@
 #include <comphelper/numbers.hxx>
 #include <comphelper/extract.hxx>
 
-#include <SpecialUnicodes.hxx>
-
 using namespace ::com::sun::star;
 
 using ::com::sun::star::uno::Reference;
@@ -90,7 +88,7 @@ OUString RegressionCurveCalculator::getFormattedString(
     double fNumber, sal_Int32* pStringLength /* = nullptr */ )
 {
     if ( pStringLength && *pStringLength <= 0 )
-        return aHashString;
+        return OUString("###");
     OUString aResult;
 
     if( xNumFormatter.is() )