[clang] [llvm] [Support] Return `LockFileManager` errors right away (PR #130627)

[Ben Langmuir via cfe-commits]

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@@ -157,42 +157,35 @@ class RemoveUniqueLockFileOnSignal {
 
 } // end anonymous namespace
 
-LockFileManager::LockFileManager(StringRef FileName)
-{
-  this->FileName = FileName;
-  if (std::error_code EC = sys::fs::make_absolute(this->FileName)) {
-    std::string S("failed to obtain absolute path for ");
-    S.append(std::string(this->FileName));
-    setError(EC, S);
-    return;
-  }
-  LockFileName = this->FileName;
+LockFileManager::LockFileManager(StringRef FileName) : FileName(FileName) {}
+
+Expected<bool> LockFileManager::tryLock() {
+  SmallString<128> AbsoluteFileName(FileName);
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benlangmuir wrote:

We should check for `tryLock` being called multiple times. 

https://github.com/llvm/llvm-project/pull/130627