Update dependencies from https://dev.azure.com/dnceng/internal/_git/dotnet-wpf-int build 20190617.15 (dotnet#1002)

- Microsoft.DotNet.Wpf.DncEng - 4.8.0-preview7.19317.15

Author: dotnet-maestro[bot]

eng/Version.Details.xml

@@ -75,9 +75,9 @@
       <Uri>https://github.com/dotnet/corefx</Uri>
       <Sha>5955ee2583d4509d37ecf55243e9e3c9af128487</Sha>
     </Dependency>
-    <Dependency Name="Microsoft.DotNet.Wpf.DncEng" Version="4.8.0-preview7.19317.4">
+    <Dependency Name="Microsoft.DotNet.Wpf.DncEng" Version="4.8.0-preview7.19317.15">
       <Uri>https://dev.azure.com/dnceng/internal/_git/dotnet-wpf-int</Uri>
-      <Sha>eecfd6f18f1520445f625591a7106c273cd28454</Sha>
+      <Sha>6a1b846653e9a595eed706f0dbf19d0f5e63570f</Sha>
     </Dependency>
     <Dependency Name="System.IO.Packaging" Version="4.6.0-preview7.19313.2" 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-preview7.19317.4</MicrosoftDotNetWpfDncEngVersion>
+    <MicrosoftDotNetWpfDncEngVersion>4.8.0-preview7.19317.15</MicrosoftDotNetWpfDncEngVersion>
   </PropertyGroup>
 </Project>