Fixed order of setting parsing context while parsing hex value

- fixes #399

Source/External/ExCSS/Parser.Blocks.cs

@@ -482,8 +482,8 @@ namespace Svg.ExCSS
                     break;
             }
 
-            ParseSingleValueHexColor(_buffer.ToString());
             SetParsingContext(ParsingContext.InSingleValue);
+            ParseSingleValueHexColor(_buffer.ToString());
             return ParseSingleValue(token);
         }
 

Tests/Svg.UnitTests/LexerIssueTests.cs

@@ -38,7 +38,6 @@ namespace Svg.UnitTests
         [TestMethod]
         public void Lexer_ImportantAfterHex_Success()
         {
-            Assert.Inconclusive("The important after the  hex codes is not working at the moment. Re-enable these tests if the issue is resolved (#399)");
             //Important should be valid on 3 digit hex
             GenerateLexerTestFile("border-top: 1px solid #333 !important;");
             //Important should be valid on 6 digit hex