[master] Update dependencies from dotnet/arcade (#2667)

* Update dependencies from https://github.com/dotnet/arcade build 20190626.44

- Microsoft.DotNet.Arcade.Sdk - 1.0.0-beta.19326.44

* Add missing feed

* Use PackageDownload

* Update dependencies from https://github.com/dotnet/arcade build 20190627.39

- Microsoft.DotNet.Arcade.Sdk - 1.0.0-beta.19327.39

* Use new apphost package and stop downloading extra packages

eng/common/post-build/trigger-subscriptions.ps1

@@ -0,0 +1,69 @@
+param(
+  [Parameter(Mandatory=$true)][string] $SourceRepo,
+  [Parameter(Mandatory=$true)][int] $ChannelId,
+  [string] $MaestroEndpoint = "https://maestro-prod.westus2.cloudapp.azure.com",
+  [string] $BarToken,
+  [string] $ApiVersion = "2019-01-16"
+)
+
+$ErrorActionPreference = "Stop"
+Set-StrictMode -Version 2.0
+
+. $PSScriptRoot\..\tools.ps1
+
+function Get-Headers([string]$accept, [string]$barToken) {
+  $headers = New-Object 'System.Collections.Generic.Dictionary[[String],[String]]'
+  $headers.Add('Accept',$accept)
+  $headers.Add('Authorization',"Bearer $barToken")
+  return $headers
+}
+
+# Get all the $SourceRepo subscriptions
+$normalizedSurceRepo = $SourceRepo.Replace('dnceng@', '')
+$getSubscriptionsApiEndpoint = "$maestroEndpoint/api/subscriptions?sourceRepository=$normalizedSurceRepo&api-version=$apiVersion"
+$headers = Get-Headers 'application/json' $barToken
+
+$subscriptions = Invoke-WebRequest -Uri $getSubscriptionsApiEndpoint -Headers $headers | ConvertFrom-Json
+
+if (!$subscriptions) {
+  Write-Host "No subscriptions found for source repo '$normalizedSurceRepo' in channel '$ChannelId'"
+  return
+}
+
+$subscriptionsToTrigger = New-Object System.Collections.Generic.List[string]
+$failedTriggeredSubscription = $false
+
+# Get all enabled subscriptions that need dependency flow on 'everyBuild'
+foreach ($subscription in $subscriptions) {
+  if ($subscription.enabled -and $subscription.policy.updateFrequency -like 'everyBuild' -and $subscription.channel.id -eq $ChannelId) {
+    Write-Host "$subscription.id"
+    [void]$subscriptionsToTrigger.Add($subscription.id)
+  }
+}
+
+foreach ($subscriptionToTrigger in $subscriptionsToTrigger) {
+  try {
+    $triggerSubscriptionApiEndpoint = "$maestroEndpoint/api/subscriptions/$subscriptionToTrigger/trigger?api-version=$apiVersion"
+    $headers = Get-Headers 'application/json' $BarToken
+    
+    Write-Host "Triggering subscription '$subscriptionToTrigger'..."
+
+    Invoke-WebRequest -Uri $triggerSubscriptionApiEndpoint -Headers $headers -Method Post
+  
+    Write-Host "Subscription '$subscriptionToTrigger' triggered!"
+  } 
+  catch
+  {
+    Write-Host "There was an error while triggering subscription '$subscriptionToTrigger'"
+    Write-Host $_
+    Write-Host $_.ScriptStackTrace
+    $failedTriggeredSubscription = $true
+  }
+}
+
+if ($failedTriggeredSubscription) {
+  Write-Host "At least one subscription failed to be triggered..."
+  ExitWithExitCode 1
+}
+
+Write-Host "All subscriptions were triggered successfully!"