[lldb] [llvm] DEBUGINFOD based DWP acquisition for LLDB (PR #70996)

[Greg Clayton via llvm-commits]

================
@@ -62,15 +66,23 @@ bool canUseDebuginfod() {
 }
 
 SmallVector<StringRef> getDefaultDebuginfodUrls() {
-  const char *DebuginfodUrlsEnv = std::getenv("DEBUGINFOD_URLS");
-  if (DebuginfodUrlsEnv == nullptr)
-    return SmallVector<StringRef>();
-
-  SmallVector<StringRef> DebuginfodUrls;
-  StringRef(DebuginfodUrlsEnv).split(DebuginfodUrls, " ");
+  if (!DebuginfodUrlsSet) {
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clayborg wrote:

If we use std::optional above, then this can be:
```
  if (!DebuginfodUrls) {
```

https://github.com/llvm/llvm-project/pull/70996