[lldb] Allow swift-clang-override-options setting when using cc1 args

When using swift caching or direct cc1 mode, allow using setting to
override clang arguments. Even this override option directly applies to
cc1 arguments, not clang driver arguments, thus is a behavior change,
but it can be handy for debugging or working around issues.

Author: cachemeifyoucan

lldb/source/Plugins/TypeSystem/Swift/SwiftASTContext.cpp

@@ -1801,11 +1801,11 @@ void SwiftASTContext::AddExtraClangArgs(
   importer_options.DirectClangCC1ModuleBuild = invocation_direct_cc1;
 
   // If using direct cc1 flags, compute the arguments and return.
-  // Since this is cc1 flags, override options are driver flags and don't apply.
   if (importer_options.DirectClangCC1ModuleBuild) {
     if (!fresh_invocation)
       importer_options.ExtraArgs.clear();
     AddExtraClangCC1Args(ExtraArgs, importer_options.ExtraArgs);
+    applyOverrideOptions(importer_options.ExtraArgs, overrideOpts);
     return;
   }
 

lldb/test/API/lang/swift/clangimporter/caching/TestSwiftClangImporterCaching.py

@@ -21,12 +21,14 @@ def test(self):
         lldbutil.run_to_source_breakpoint(self, "break here",
                                           lldb.SBFileSpec('main.swift'))
         log = self.getBuildArtifact("types.log")
+        self.runCmd("settings set target.swift-clang-override-options +-DADDED=1")
         self.expect('log enable lldb types -f "%s"' % log)
         self.expect("expression obj", DATA_TYPES_DISPLAYED_CORRECTLY,
                     substrs=["b ="])
         self.filecheck('platform shell cat "%s"' % log, __file__)
 ### -cc1 should be round-tripped so there is no more `-cc1` in the extra args. Look for `-triple` which is a cc1 flag.
 #       CHECK:  SwiftASTContextForExpressions(module: "a", cu: "main.swift")::LogConfiguration() --     -triple
+#       CHECK:  SwiftASTContextForExpressions(module: "a", cu: "main.swift")::LogConfiguration() --     -DADDED=1
 #       CHECK:  SwiftASTContextForExpressions(module: "a", cu: "main.swift") Module import remark: loaded module 'ClangA'
 #       CHECK-NOT: -cc1
 #       CHECK-NOT: -fmodule-file-cache-key