[clang] [clang][Parser] "Better" error messages for invalid template template (PR #95726)

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@@ -787,6 +787,20 @@ NamedDecl *Parser::ParseTemplateTemplateParameter(unsigned Depth,
                                                   unsigned Position) {
   assert(Tok.is(tok::kw_template) && "Expected 'template' keyword");
 
+  if (Token ahead = GetLookAheadToken(1); ahead.isNot(tok::less)) {
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Sirraide wrote:

One more thing, I somehow forgot to comment on this earlier, but we typically use PascalCase for variables, so this should be `Ahead` (though I’d probably call it `Next` or sth, but that’s not that important...).

https://github.com/llvm/llvm-project/pull/95726