Fix unit test failure from merge

src/Compilers/CSharp/Test/Semantic/IOperation/IOperationTests_IAwaitExpression.cs

@@ -194,7 +194,7 @@ static void M(Task<int> t)
 ";
             string expectedOperationTree = @"
 IVariableDeclarationStatement (1 declarations) (OperationKind.VariableDeclarationStatement, IsInvalid) (Syntax: 'await t;')
-  IVariableDeclaration (1 variables) (OperationKind.VariableDeclaration, IsInvalid) (Syntax: 'await t;')
+  IVariableDeclaration (1 variables) (OperationKind.VariableDeclaration, IsInvalid) (Syntax: 't')
     Variables: Local_1: await t
     Initializer: null
 ";