[clang] [clang][modulemap] Lazily load module maps by header name (PR #181916)

[Jan Svoboda via cfe-commits]

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@@ -1698,12 +1838,9 @@ HeaderSearch::findResolvedModulesForHeader(FileEntryRef File) const {
   return ModMap.findResolvedModulesForHeader(File);
 }
 
-static bool suggestModule(HeaderSearch &HS, FileEntryRef File,
-                          Module *RequestingModule,
+static bool suggestModule(HeaderSearch &HS, ModuleMap::KnownHeader Module,
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jansvoboda11 wrote:

Would it make sense to keep the old function around and look up the `KnownHeader` in it, to keep the existing callers unchanged? I guess there's only one caller outside of this function, so there's not much benefit?

https://github.com/llvm/llvm-project/pull/181916