Cleanup and documentation from code review

src/Workspaces/Core/Portable/TemporaryStorage/TemporaryStorageServiceFactory.cs

@@ -210,7 +210,7 @@ public ImmutableArray<byte> GetChecksum()
                 {
                     if (_checksum.IsDefault)
                     {
-                        _checksum = ReadText(CancellationToken.None).GetChecksum();
+                        ImmutableInterlocked.InterlockedInitialize(ref _checksum, ReadText(CancellationToken.None).GetChecksum());
                     }
 
                     return _checksum;

src/Workspaces/Core/Portable/Workspace/Host/TemporaryStorage/ITemporaryTextStorageWithName.cs

@@ -10,12 +10,27 @@
 
 namespace Microsoft.CodeAnalysis.Host
 {
+    /// <summary>
+    /// Represents a <see cref="ITemporaryStorageWithName"/> which is used to hold data for <see cref="SourceText"/>.
+    /// </summary>
     internal interface ITemporaryTextStorageWithName : ITemporaryTextStorage, ITemporaryStorageWithName
     {
+        /// <summary>
+        /// Gets the value for the <see cref="SourceText.ChecksumAlgorithm"/> property for the <see cref="SourceText"/>
+        /// represented by this temporary storage.
+        /// </summary>
         SourceHashAlgorithm ChecksumAlgorithm { get; }
 
+        /// <summary>
+        /// Gets the value for the <see cref="SourceText.Encoding"/> property for the <see cref="SourceText"/>
+        /// represented by this temporary storage.
+        /// </summary>
         Encoding? Encoding { get; }
 
+        /// <summary>
+        /// Gets the checksum for the <see cref="SourceText"/> represented by this temporary storage. This is equivalent
+        /// to calling <see cref="SourceText.GetChecksum"/>.
+        /// </summary>
         ImmutableArray<byte> GetChecksum();
     }
 }

src/Workspaces/Remote/Core/AbstractAssetProvider.cs

@@ -98,10 +98,11 @@ public async Task<DocumentInfo> CreateDocumentInfoAsync(Checksum documentChecksu
         {
             var documentSnapshot = await GetAssetAsync<DocumentStateChecksums>(documentChecksum, cancellationToken).ConfigureAwait(false);
             var documentInfo = await GetAssetAsync<DocumentInfo.DocumentAttributes>(documentSnapshot.Info, cancellationToken).ConfigureAwait(false);
+            var serializableSourceText = await GetAssetAsync<SerializableSourceText>(documentSnapshot.Text, cancellationToken).ConfigureAwait(false);
 
             var textLoader = TextLoader.From(
                 TextAndVersion.Create(
-                    await (await GetAssetAsync<SerializableSourceText>(documentSnapshot.Text, cancellationToken).ConfigureAwait(false)).GetTextAsync(cancellationToken).ConfigureAwait(false),
+                    await serializableSourceText.GetTextAsync(cancellationToken).ConfigureAwait(false),
                     VersionStamp.Create(),
                     documentInfo.FilePath));
 

src/Workspaces/Remote/Core/SolutionAsset.cs

@@ -33,6 +33,10 @@ internal sealed class SolutionAsset
 
         public SolutionAsset(object? value, Checksum checksum, WellKnownSynchronizationKind kind)
         {
+            // SolutionAsset is not allowed to hold strong references to SourceText. SerializableSourceText is used
+            // instead to allow data to be released from process address space when it is also held in temporary
+            // storage.
+            // https://github.com/dotnet/roslyn/issues/43802
             Contract.ThrowIfTrue(kind is WellKnownSynchronizationKind.SourceText);
 
             Checksum = checksum;