fdo#82858 RTF export: fix "none" line style of TextFrames

Regression from commit 9e6a5b94
(RtfAttributeOutput::FormatBox: export line{Color,Width} shape
properties, 2013-04-15), in case lineColor is written, but there is no
border style, then an explicit fLine=0 property is needed, otherwise a
black border shows up.

Change-Id: I6d6eedbc8d3ee4bee0f2aadb51a376c7734c6640

sw/CppunitTest_sw_rtfexport.mk

@@ -76,6 +76,7 @@ $(eval $(call gb_CppunitTest_use_components,sw_rtfexport,\
 	uui/util/uui \
     writerfilter/util/writerfilter \
     xmloff/util/xo \
+	oox/util/oox \
 ))
 
 $(eval $(call gb_CppunitTest_use_configuration,sw_rtfexport))

sw/qa/extras/rtfexport/rtfexport.cxx

@@ -719,6 +719,12 @@ DECLARE_RTFEXPORT_TEST(testFdo82860, "fdo82860.odt")
     CPPUNIT_ASSERT_EQUAL(OUString("hello"), getParagraphOfText(1, xText)->getString());
 }
 
+DECLARE_RTFEXPORT_TEST(testFdo82858, "fdo82858.docx")
+{
+    // This was table::BorderLineStyle::SOLID, exporter failed to write explicit no line when line color was written.
+    CPPUNIT_ASSERT_EQUAL(table::BorderLineStyle::NONE, getProperty<table::BorderLine2>(getShape(1), "TopBorder").LineStyle);
+}
+
 CPPUNIT_PLUGIN_IMPLEMENT();
 
 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */

sw/source/filter/ww8/rtfattributeoutput.cxx

@@ -3104,6 +3104,9 @@ void RtfAttributeOutput::FormatBox(const SvxBoxItem& rBox)
                 sal_Int32 nWidth = sal_Int32(fConverted * 635); // Twips -> EMUs
                 m_aFlyProperties.push_back(std::make_pair<OString, OString>("lineWidth", OString::number(nWidth)));
             }
+            else
+                // No border: no line.
+                m_aFlyProperties.push_back(std::make_pair<OString, OString>("fLine", "0"));
         }
 
         return;