[lld] [LLD][COFF] Store reference to SymbolTable instead of COFFLinkerContext in InputFile (NFC) (PR #119296)

[Jacek Caban via llvm-commits]

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@@ -403,8 +404,8 @@ class BitcodeFile : public InputFile {
 // .dll file. MinGW only.
 class DLLFile : public InputFile {
 public:
-  explicit DLLFile(COFFLinkerContext &ctx, MemoryBufferRef m)
-      : InputFile(ctx, DLLKind, m) {}
+  explicit DLLFile(SymbolTable &symtab, MemoryBufferRef m)
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cjacek wrote:

Ah, I remember now why I didn't change it: the constructor would need to be moved out of the header because `COFFLinkerContext` is an incomplete type in `InputFiles.h`. Since it will ultimately use the `symtab` argument (as mentioned above), I updated the type in this commit already. Should I change it?

https://github.com/llvm/llvm-project/pull/119296