vs fix

proj.win32/oxygine-sound.vcxproj

@@ -12,6 +12,7 @@
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="..\src\sound\MemoryStream.h" />
+    <ClInclude Include="..\src\sound\null\SoundHandleNull.h" />
     <ClInclude Include="..\src\sound\null\SoundNull.h" />
     <ClInclude Include="..\src\sound\null\SoundSystemNull.h" />
     <ClInclude Include="..\src\sound\oal.h" />
@@ -33,6 +34,7 @@
   </ItemGroup>
   <ItemGroup>
     <ClCompile Include="..\src\sound\MemoryStream.cpp" />
+    <ClCompile Include="..\src\sound\null\SoundHandleNull.cpp" />
     <ClCompile Include="..\src\sound\null\SoundNull.cpp" />
     <ClCompile Include="..\src\sound\null\SoundSystemNull.cpp" />
     <ClCompile Include="..\src\sound\oal\SoundHandleOAL.cpp" />

proj.win32/oxygine-sound.vcxproj.filters

@@ -69,6 +69,9 @@
     <ClInclude Include="..\src\sound\oal\SoundSystemOAL.h">
       <Filter>sound\oal</Filter>
     </ClInclude>
+    <ClInclude Include="..\src\sound\null\SoundHandleNull.h">
+      <Filter>sound\null</Filter>
+    </ClInclude>
   </ItemGroup>
   <ItemGroup>
     <ClCompile Include="..\src\sound\MemoryStream.cpp">
@@ -119,5 +122,8 @@
     <ClCompile Include="..\src\sound\SoundSystem.cpp">
       <Filter>sound</Filter>
     </ClCompile>
+    <ClCompile Include="..\src\sound\null\SoundHandleNull.cpp">
+      <Filter>sound\null</Filter>
+    </ClCompile>
   </ItemGroup>
 </Project>