Add -prefix-serialized-debugging-options (#39555)

This commit adds a new frontend flag that applies debug path prefixing to the
paths serialized in swiftmodule files. This makes it possible to use swiftmodule
files that have been built on different machines by applying the inverse map
when debugging, in a similar fashion to source path prefixing.

The inverse mapping in LLDB will be handled in a follow up PR.

Second pass at #39138

Tests updated to handle windows path separators.

This reverts commit f5aa95b381.

lib/Basic/LangOptions.cpp

@@ -408,3 +408,56 @@ DiagnosticBehavior LangOptions::getAccessNoteFailureLimit() const {
   }
   llvm_unreachable("covered switch");
 }
+
+std::vector<std::string> ClangImporterOptions::getRemappedExtraArgs(
+    std::function<std::string(StringRef)> pathRemapCallback) const {
+  auto consumeIncludeOption = [](StringRef &arg, StringRef &prefix) {
+    static StringRef options[] = {"-I",
+                                  "-F",
+                                  "-fmodule-map-file=",
+                                  "-iquote",
+                                  "-idirafter",
+                                  "-iframeworkwithsysroot",
+                                  "-iframework",
+                                  "-iprefix",
+                                  "-iwithprefixbefore",
+                                  "-iwithprefix",
+                                  "-isystemafter",
+                                  "-isystem",
+                                  "-isysroot",
+                                  "-ivfsoverlay",
+                                  "-working-directory=",
+                                  "-working-directory"};
+    for (StringRef &option : options)
+      if (arg.consume_front(option)) {
+        prefix = option;
+        return true;
+      }
+    return false;
+  };
+
+  // true if the previous argument was the dash-option of an option pair
+  bool remap_next = false;
+  std::vector<std::string> args;
+  for (auto A : ExtraArgs) {
+    StringRef prefix;
+    StringRef arg(A);
+
+    if (remap_next) {
+      remap_next = false;
+      args.push_back(pathRemapCallback(arg));
+    } else if (consumeIncludeOption(arg, prefix)) {
+      if (arg.empty()) {
+        // Option pair
+        remap_next = true;
+        args.push_back(prefix.str());
+      } else {
+        // Combine prefix with remapped path value
+        args.push_back(prefix.str() + pathRemapCallback(arg));
+      }
+    } else {
+      args.push_back(A);
+    }
+  }
+  return args;
+}