Update dependencies from...

Update dependencies from https://dev.azure.com/dnceng/internal/_git/dotnet-wpf-int build 20190612.6 (#944)

- Microsoft.DotNet.Wpf.DncEng - 4.8.0-preview7.19312.6

eng/Version.Details.xml

@@ -75,9 +75,9 @@
       <Uri>https://github.com/dotnet/corefx</Uri>
       <Sha>550c5f5fcc9d5b552be749a1b0c49d6f31e38ade</Sha>
     </Dependency>
-    <Dependency Name="Microsoft.DotNet.Wpf.DncEng" Version="4.8.0-preview7.19311.6">
+    <Dependency Name="Microsoft.DotNet.Wpf.DncEng" Version="4.8.0-preview7.19312.6">
       <Uri>https://dev.azure.com/dnceng/internal/_git/dotnet-wpf-int</Uri>
-      <Sha>95764b755a2cd678f40e2a2cfc83d17672e511da</Sha>
+      <Sha>3204af57b16e48251dd355fef00d3d8289659ee9</Sha>
     </Dependency>
     <Dependency Name="System.IO.Packaging" Version="4.6.0-preview7.19312.5" CoherentParentDependency="Microsoft.NETCore.App">
       <Uri>https://github.com/dotnet/corefx</Uri>

eng/Versions.props

@@ -105,6 +105,6 @@
       It is worth reiterating that this package *should not* be consumed to build the product.
   -->
   <PropertyGroup>
-    <MicrosoftDotNetWpfDncEngVersion>4.8.0-preview7.19311.6</MicrosoftDotNetWpfDncEngVersion>
+    <MicrosoftDotNetWpfDncEngVersion>4.8.0-preview7.19312.6</MicrosoftDotNetWpfDncEngVersion>
   </PropertyGroup>
 </Project>