Made IFormattingFilter sync

While plumbing through a CancellationToken I noticed that
IFormattingFilter had no async implementations.  Made it sync until an
actual async version is needed.

Author: jaredpar

src/Microsoft.DotNet.CodeFormatting/Filters/FilenameFilter.cs

@@ -21,11 +21,11 @@ public FilenameFilter(IEnumerable<string> filenames)
             _filenames = filenames;
         }
 
-        public Task<bool> ShouldBeProcessedAsync(Document document)
+        public bool ShouldBeProcessed(Document document)
         {
             if (!_filenames.Any())
             {
-                return Task.FromResult(true);
+                return true;
             }
 
             string docFilename = Path.GetFileName(document.FilePath);
@@ -34,11 +34,11 @@ public Task<bool> ShouldBeProcessedAsync(Document document)
             {
                 if (filename.Equals(docFilename, StringComparison.InvariantCultureIgnoreCase))
                 {
-                    return Task.FromResult(true);
+                    return true;
                 }
             }
 
-            return Task.FromResult(false);
+            return false;
         }
     }
 }

src/Microsoft.DotNet.CodeFormatting/Filters/IgnoreDesignerGeneratedCodeFilter.cs

@@ -12,15 +12,15 @@ namespace Microsoft.DotNet.CodeFormatting.Filters
     [Export(typeof(IFormattingFilter))]
     internal sealed class IgnoreDesignerGeneratedCodeFilter : IFormattingFilter
     {
-        public Task<bool> ShouldBeProcessedAsync(Document document)
+        public bool ShouldBeProcessed(Document document)
         {
             if (document.FilePath == null)
             {
-                return Task.FromResult(true);
+                return true;
             }
 
             var isDesignerGenerated = document.FilePath.EndsWith(".Designer.cs", StringComparison.OrdinalIgnoreCase);
-            return Task.FromResult(!isDesignerGenerated);
+            return !isDesignerGenerated;
         }
     }
 }

src/Microsoft.DotNet.CodeFormatting/FormattingEngineImplementation.cs

@@ -125,7 +125,7 @@ private async Task SaveChanges(Solution solution, Solution originalSolution, Can
             }
         }
 
-        private async Task<bool> ShouldBeProcessedAsync(Document document)
+        private bool ShouldBeProcessed(Document document)
         {
             if (document.FilePath != null)
             {
@@ -141,22 +141,22 @@ private async Task<bool> ShouldBeProcessedAsync(Document document)
 
             foreach (var filter in _filters)
             {
-                var shouldBeProcessed = await filter.ShouldBeProcessedAsync(document);
+                var shouldBeProcessed = filter.ShouldBeProcessed(document);
                 if (!shouldBeProcessed)
                     return false;
             }
 
             return true;
         }
 
-        private async Task<SyntaxNode> GetSyntaxRootAndFilter(Document document, CancellationToken cancellationToken)
+        private Task<SyntaxNode> GetSyntaxRootAndFilter(Document document, CancellationToken cancellationToken)
         {
-            if (!await ShouldBeProcessedAsync(document))
+            if (!ShouldBeProcessed(document))
             {
                 return null;
             }
 
-            return await document.GetSyntaxRootAsync(cancellationToken);
+            return document.GetSyntaxRootAsync(cancellationToken);
         }
 
         private void StartDocument()

src/Microsoft.DotNet.CodeFormatting/IFormattingFilter.cs

@@ -8,9 +8,8 @@
 
 namespace Microsoft.DotNet.CodeFormatting
 {
-    // TODO: does this need to be async? 
     internal interface IFormattingFilter
     {
-        Task<bool> ShouldBeProcessedAsync(Document document);
+        bool ShouldBeProcessed(Document document);
     }
 }

src/Microsoft.DotNet.CodeFormatting/Rules/RuleExtensions.cs

@@ -24,10 +24,5 @@ public static IEnumerable<SyntaxTrivia> AddNewLine(this IEnumerable<SyntaxTrivia
         {
             return trivia.Concat(new[] { SyntaxFactory.CarriageReturnLineFeed });
         }
-
-        public static IEnumerable<SyntaxTrivia> AddWhiteSpaceTrivia(this IEnumerable<SyntaxTrivia> trivia)
-        {
-            return trivia.Concat(new[] { SyntaxFactory.Tab });
-        }
     }
 }