support for ms binary format validation in chart2 module export tests

Validation is done with Microsoft Office Binary File Format Validator if it
is enabled. However binary files are failing validation, so validation is
disbled in corresponding tests.

Change-Id: I9f6ff5c3dd9e3e3c0bb37ce895e60e38a0b43e9a
Reviewed-on: https://gerrit.libreoffice.org/26510
Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Thorsten Behrens <Thorsten.Behrens@CIB.de>

chart2/qa/extras/chart2export.cxx

@@ -468,6 +468,7 @@ void Chart2ExportTest::testTrendlineOOXML()
 
 void Chart2ExportTest::testTrendlineXLS()
 {
+    mbSkipValidation = true;
     load("/chart2/qa/extras/data/ods/", "trendline.ods");
     checkTrendlinesInChart(getChartDocFromSheet( 0, mxComponent));
     reload("MS Excel 97");

chart2/qa/extras/charttest.hxx

@@ -150,7 +150,11 @@ std::shared_ptr<utl::TempFile> ChartTest::reload(const OUString& rFilterName)
         if(!mbSkipValidation)
             validate(pTempFile->GetFileName(), test::ODF);
     }
-
+    else if(rFilterName == "MS Excel 97")
+    {
+        if(!mbSkipValidation)
+            validate(pTempFile->GetFileName(), test::MSBINARY);
+    }
     CPPUNIT_ASSERT(mxComponent.is());
     return pTempFile;
 }