[clang] [clang-tools-extra] [clang][DependencyScanning] Use `DependencyConsumer` to Gather Results for the By-Name Drain (PR #210458)

[Qiongsi Wu via cfe-commits]

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@@ -89,7 +121,7 @@ class DependencyScanningWorker {
   /// The tracing VFS overlaid on top of the base VFS.
   IntrusiveRefCntPtr<llvm::vfs::TracingFileSystem> TracingFS;
 
-  friend tooling::CompilerInstanceWithContext;
+  friend class CompilerInstanceWithContext;
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qiongsiwu wrote:

Actually we do need this for the CIWC to access the worker's `Service` member to access the logger. Keeping it. 

https://github.com/llvm/llvm-project/pull/210458