Serialize project state from VS to project.razor.json (dotnet/razor#1711)

Serialize project state to project.razor.json\n\nCommit migrated from dotnet/razor@fef50ba

Author: ryanbrandenburg

src/Razor/perf/Microsoft.AspNetCore.Razor.Performance/ProjectSystem/ProjectSnapshotManagerBenchmarkBase.cs

@@ -12,6 +12,7 @@
 using Microsoft.CodeAnalysis.Host;
 using Microsoft.CodeAnalysis.Razor;
 using Microsoft.CodeAnalysis.Razor.ProjectSystem;
+using Microsoft.CodeAnalysis.Razor.Serialization;
 using Microsoft.CodeAnalysis.Text;
 using Microsoft.VisualStudio.LanguageServices.Razor.Serialization;
 using Newtonsoft.Json;

src/Razor/perf/Microsoft.AspNetCore.Razor.Performance/TagHelperSerializationBenchmark.cs

@@ -7,6 +7,7 @@
 using System.Text;
 using BenchmarkDotNet.Attributes;
 using Microsoft.AspNetCore.Razor.Language;
+using Microsoft.CodeAnalysis.Razor.Serialization;
 using Microsoft.VisualStudio.LanguageServices.Razor.Serialization;
 using Newtonsoft.Json;