Merge remote-tracking branch 'upstream/release/3.0' into merge-to-31

diff --cc eng/Version.Details.xml
index c9bbd13,8a02dd6..3cdbe93
--- 1/eng/Version.Details.xml
--- 2/eng/Version.Details.xml
+++ b/eng/Version.Details.xml
@@@ -18,19 -18,19 +18,19 @@@
        <Uri>https://github.com/dotnet/arcade</Uri>
        <Sha>8eb29ba860a3cfcfe68f9a8256caa7efc1f1aaba</Sha>
      </Dependency>
 -    <Dependency Name="Microsoft.Private.CoreFx.NETCoreApp" Version="4.6.0-rc2.19461.13">
 +    <Dependency Name="Microsoft.Private.CoreFx.NETCoreApp" Version="4.7.0-preview1.19461.12">
        <Uri>https://github.com/dotnet/corefx</Uri>
 -      <Sha>144ebb6ff997bf7a777206a233cdd8c03e13f60c</Sha>
 +      <Sha>57c36a6816a5ac6d0a7956ae1e153c6a770332be</Sha>
      </Dependency>
 -    <Dependency Name="Microsoft.NETCore.Platforms" Version="3.0.0-rc2.19461.13">
 +    <Dependency Name="Microsoft.NETCore.Platforms" Version="3.1.0-preview1.19461.12">
        <Uri>https://github.com/dotnet/corefx</Uri>
 -      <Sha>144ebb6ff997bf7a777206a233cdd8c03e13f60c</Sha>
 +      <Sha>57c36a6816a5ac6d0a7956ae1e153c6a770332be</Sha>
      </Dependency>
 -    <Dependency Name="Microsoft.NETCore.App" Version="3.0.0-rc2-19460-02">
 +    <Dependency Name="Microsoft.NETCore.App" Version="3.1.0-preview1.19459.38">
        <Uri>https://github.com/dotnet/core-setup</Uri>
 -      <Sha>4421cfb105df112492038e5c5a70c24bce48e72f</Sha>
 +      <Sha>0d6763312a2754e45d604ebdc69c8ac7e21a2187</Sha>
      </Dependency>
-     <Dependency Name="optimization.IBC.CoreCLR" Version="99.99.99-master-20190910.1">
+     <Dependency Name="optimization.IBC.CoreCLR" Version="99.99.99-master-20190912.1">
        <Uri>https://dev.azure.com/dnceng/internal/_git/dotnet-optimization</Uri>
        <Sha>48fd58c24cddbc6c0b0de1c00204aae1170f4864</Sha>
      </Dependency>

diff --cc eng/Versions.props
Simple merge