Allow passing default value to Bench::GetXXXParameter()

Just an extra convenience for the benchmark functions.

tests/benchmarks/bench.cpp

@@ -87,14 +87,16 @@ wxIMPLEMENT_APP_CONSOLE(BenchApp);
 
 Bench::Function *Bench::Function::ms_head = NULL;
 
-long Bench::GetNumericParameter()
+long Bench::GetNumericParameter(long defVal)
 {
-    return wxGetApp().GetNumericParameter();
+    const long val = wxGetApp().GetNumericParameter();
+    return val ? val : defVal;
 }
 
-wxString Bench::GetStringParameter()
+wxString Bench::GetStringParameter(const wxString& defVal)
 {
-    return wxGetApp().GetStringParameter();
+    const wxString& val = wxGetApp().GetStringParameter();
+    return !val.empty() ? val : defVal;
 }
 
 // ============================================================================

tests/benchmarks/bench.h

@@ -83,7 +83,7 @@ private:
     Tests may use this parameter in whatever way they see fit, by default it is
     1 but can be set to a different value by user from the command line.
  */
-long GetNumericParameter();
+long GetNumericParameter(long defValue = 1);
 
 /**
     Get the string parameter.
@@ -91,7 +91,7 @@ long GetNumericParameter();
     Tests may use this parameter in whatever way they see fit, by default it is
     empty but can be set to a different value by user from the command line.
  */
-wxString GetStringParameter();
+wxString GetStringParameter(const wxString& defValue = wxString());
 
 } // namespace Bench