Backwards compat runtimes should not come from product construction sources

Author: mmitche

build/AzureInfo.props

@@ -1,8 +1,10 @@
 <Project ToolsVersion="15.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <PropertyGroup>
     <Product>Sdk</Product>
+    <DefaultCoreSetupBlobRootUrl>https://dotnetcli.azureedge.net/dotnet/</DefaultCoreSetupBlobRootUrl>
     <CoreSetupBlobRootUrl Condition="'$(PB_AssetRootUrl)' != ''">$(PB_AssetRootUrl)</CoreSetupBlobRootUrl>
-    <CoreSetupBlobRootUrl Condition="'$(CoreSetupBlobRootUrl)' == ''">https://dotnetcli.azureedge.net/dotnet/</CoreSetupBlobRootUrl>
+    <CoreSetupBlobRootUrl Condition="'$(CoreSetupBlobRootUrl)' == ''">$(DefaultCoreSetupBlobRootUrl)</CoreSetupBlobRootUrl>
+    <BackwardsCompatibilityCoreSetupBlobRootUrl>$(DefaultCoreSetupBlobRootUrl)</BackwardsCompatibilityCoreSetupBlobRootUrl>
     <CoreSetupBlobAccessToken Condition="'$(PB_AssetRootAccessTokenSuffix)' != ''">$(PB_AssetRootAccessTokenSuffix)</CoreSetupBlobAccessToken>
     <CoreSetupBlobAccessTokenParam Condition=" '$(CoreSetupBlobAccessToken)' != '' ">?$(CoreSetupBlobAccessToken)</CoreSetupBlobAccessTokenParam>
     <ArtifactContainerName>$(ARTIFACT_STORAGE_CONTAINER)</ArtifactContainerName>

build/BackwardsCompatibilityRuntimes.props

@@ -16,7 +16,7 @@
 
     <BackwardsCompatibility110CombinedFrameworkHostCompressedFileName>dotnet-$(HostMonikerRid).$(BackwardsCompatibility110SharedFrameworkVersion)$(ArchiveExtension)</BackwardsCompatibility110CombinedFrameworkHostCompressedFileName>
 
-    <BackwardsCompatibility110CoreSetupBlobRootUrlWithChannel>$(CoreSetupBlobRootUrl)$(BackwardsCompatibility110CoreSetupChannel)</BackwardsCompatibility110CoreSetupBlobRootUrlWithChannel>
+    <BackwardsCompatibility110CoreSetupBlobRootUrlWithChannel>$(BackwardsCompatibilityCoreSetupBlobRootUrl)$(BackwardsCompatibility110CoreSetupChannel)</BackwardsCompatibility110CoreSetupBlobRootUrlWithChannel>
     <BackwardsCompatibility110SharedFrameworkArchiveBlobRootUrl>$(BackwardsCompatibility110CoreSetupBlobRootUrlWithChannel)/Binaries/$(BackwardsCompatibility110SharedFrameworkVersion)</BackwardsCompatibility110SharedFrameworkArchiveBlobRootUrl>
     <BackwardsCompatibility110CoreSetupInstallerBlobRootUrl>$(BackwardsCompatibility110CoreSetupBlobRootUrlWithChannel)/Installers</BackwardsCompatibility110CoreSetupInstallerBlobRootUrl>
     <BackwardsCompatibility110CoreSetupDownloadDirectory>$(IntermediateDirectory)/coreSetupDownload/$(BackwardsCompatibility110SharedFrameworkVersion)</BackwardsCompatibility110CoreSetupDownloadDirectory>