Simplify code that calls out to third party extensions.

src/EditorFeatures/Core/FindUsages/AbstractFindUsagesService.cs

@@ -47,33 +47,37 @@ public async Task FindImplementationsAsync(Document document, int position, IFin
         public async Task FindReferencesAsync(
             Document document, int position, IFindUsagesContext context)
         {
+            var definitionTrackingContext = new DefinitionTrackingContext(context);
+
             // NOTE: All ConFigureAwaits in this method need to pass 'true' so that
             // we return to the caller's context.  that's so the call to 
             // CallThirdPartyExtensionsAsync will happen on the UI thread.  We need
             // this to maintain the threading guarantee we had around that method
             // from pre-Roslyn days.
-            var cancellationToken = context.CancellationToken;
-            cancellationToken.ThrowIfCancellationRequested();
+            await FindLiteralOrSymbolReferencesAsync(
+                document, position, definitionTrackingContext).ConfigureAwait(true);
+
+            // After the FAR engine is done call into any third party extensions to see
+            // if they want to add results.
+            await CallThirdPartyExtensionsAsync( 
+                document.Project.Solution, definitionTrackingContext, context).ConfigureAwait(true);
+        }
 
+        private async Task FindLiteralOrSymbolReferencesAsync(
+            Document document, int position, IFindUsagesContext context)
+        {
             // First, see if we're on a literal.  If so search for literals in the solution with
             // the same value.
-            var found = await TryFindLiteralReferencesAsync(document, position, context).ConfigureAwait(true);
+            var found = await TryFindLiteralReferencesAsync(
+                document, position, context).ConfigureAwait(false);
             if (found)
             {
                 return;
             }
 
-            var definitionTrackingContext = new DefinitionTrackingContext(context);
-
-            // ConfigureAwait(true) because we want to come back on the same thread before calling 
-            // into extensions.
+            // Wasn't a literal.  Try again as a symbol.
             await FindSymbolReferencesAsync(
-                document, position, definitionTrackingContext).ConfigureAwait(true);
-
-            // After the FAR engine is done call into any third party extensions to see
-            // if they want to add results.
-            await CallThirdPartyExtensionsAsync( 
-                document.Project.Solution, definitionTrackingContext, context).ConfigureAwait(true);
+                document, position, context).ConfigureAwait(false);
         }
 
         private async Task CallThirdPartyExtensionsAsync(
@@ -86,8 +90,7 @@ public async Task FindImplementationsAsync(Document document, int position, IFin
 
             foreach (var definition in definitionTrackingContext.GetDefinitions())
             {
-                var item = factory.GetThirdPartyDefinitionItem(
-                    solution, definition, cancellationToken);
+                var item = factory.GetThirdPartyDefinitionItem(solution, definition, cancellationToken);
                 if (item != null)
                 {
                     // ConfigureAwait(true) because we want to come back on the