[clang] [clang-format] Improve function pointer CastRParen detection. (PR #126019)

[Owen Pan via cfe-commits]

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@@ -874,6 +874,11 @@ TEST_F(TokenAnnotatorTest, UnderstandsCasts) {
   EXPECT_TOKEN(Tokens[14], tok::r_paren, TT_CastRParen);
   EXPECT_TOKEN(Tokens[15], tok::amp, TT_UnaryOperator);
 
+  Tokens = annotate("func((foo(bar::*)(void))&a);");
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owenca wrote:

So `foo` is a return type. Then the `(` that follows should be annotated as a `FunctionLParen`, and there should be a space between them like in `int (*)()`.

https://github.com/llvm/llvm-project/pull/126019