Preserve type arguments in generic invocation expressions.

lib/src/source_visitor.dart

Index: lib/src/source_visitor.dart
diff --git a/lib/src/source_visitor.dart b/lib/src/source_visitor.dart
index 213f7a420eb9e28a74e7db779dbb3af67b4811ca..f78627e6775ff03d1d8d60025a7b211de2592a1d 100644
--- a/lib/src/source_visitor.dart
+++ b/lib/src/source_visitor.dart
@@ -1151,8 +1151,16 @@ class SourceVisitor extends ThrowingAstVisitor {
   }
 
   visitFunctionExpressionInvocation(FunctionExpressionInvocation node) {
+    // Try to keep the entire invocation one line.
+    builder.startSpan();
+    builder.nestExpression();
+
     visit(node.function);
-    visit(node.argumentList);
+    visit(node.typeArguments);
+    visitArgumentList(node.argumentList, nestExpression: false);
+
+    builder.unnest();
+    builder.endSpan();
   }
 
   visitFunctionTypeAlias(FunctionTypeAlias node) {