Support tailoring clang --target flag based on min sdk version.

Bug: 215748260
Test: Tested using aquery to verify the --target flag; add added unit

Change-Id: Ifb13509db7d1e110316aa44d55ec9cccaa4b83d1
diff --git a/cc/library_headers.go b/cc/library_headers.go
index 5d38fba..41ebcc7 100644
--- a/cc/library_headers.go
+++ b/cc/library_headers.go
@@ -117,6 +117,7 @@
 	Deps                     bazel.LabelListAttribute
 	Implementation_deps      bazel.LabelListAttribute
 	System_dynamic_deps      bazel.LabelListAttribute
+	sdkAttributes
 }
 
 func libraryHeadersBp2Build(ctx android.TopDownMutatorContext, module *Module) {
@@ -132,6 +133,7 @@
 		Deps:                     linkerAttrs.deps,
 		System_dynamic_deps:      linkerAttrs.systemDynamicDeps,
 		Hdrs:                     baseAttributes.hdrs,
+		sdkAttributes:            bp2BuildParseSdkAttributes(module),
 	}
 
 	props := bazel.BazelTargetModuleProperties{