[clang] [Clang][Preprocessor] Unify header-name lookahead for import and include (PR #191004)

[Yihan Wang via cfe-commits]

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@@ -4695,11 +4696,17 @@ bool Lexer::LexDependencyDirectiveToken(Token &Result) {
     MIOpt.ReadToken();
   }
 
-  if (ParsingFilename && DDTok.is(tok::less)) {
-    BufferPtr = BufferStart + DDTok.Offset;
-    LexAngledStringLiteral(Result, BufferPtr + 1);
-    if (Result.isNot(tok::header_name))
+  const char *DDTokPtr = BufferStart + DDTok.Offset;
+  if (ParsingFilename && *DDTokPtr == '<') {
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yronglin wrote:

I have add a new test for dep-scan, we don't need a `SkipEscapedNewLines`, because DDTok.Offset already skipped the escaped new line.

https://github.com/llvm/llvm-project/pull/191004