Fix code for clang-tidy warnings

After clang-r498229, we got below new warnings:
art/artd/artd.cc:810:42: error: redundant call to 'c_str'
  [readability-redundant-string-cstr,-warnings-as-errors]
    context = ClassLoaderContext::Create(in_classLoaderContext->c_str());
                                         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
                                         *in_classLoaderContext->
art/artd/artd.cc:899:35: error: redundant call to 'c_str'
  [readability-redundant-string-cstr,-warnings-as-errors]
    std::string dex_dir = Dirname(in_dexFile.c_str());
                                  ^~~~~~~~~~~~~~~~~~
                                  in_dexFile

art/artd/artd_test.cc:75:42: error: using decl 'GetDexoptStatusResult' is unused
  [misc-unused-using-decls,-warnings-as-errors]
using ::aidl::com::android::server::art::GetDexoptStatusResult;
                                         ^

art/artd/path_utils_test.cc:31:42: error: using decl 'VdexPath' is unused
  [misc-unused-using-decls,-warnings-as-errors]
using ::aidl::com::android::server::art::VdexPath;
                                         ^

art/artd/artd_test.cc:394:15: error: parameter 'cancellation_signal' is passed by value
and only copied once; consider moving it to avoid unnecessary copies
[performance-unnecessary-value-param,-warnings-as-errors]
              cancellation_signal);
              ^
              std::move(         )

Bug: 285008138
Test: build with WITH_TIDY=1
Change-Id: Id17bfea4dc78175aec3b1328e916f8c574e61a8c
diff --git a/artd/artd.cc b/artd/artd.cc
index 5d65b4f..afed965 100644
--- a/artd/artd.cc
+++ b/artd/artd.cc
@@ -807,7 +807,7 @@
 
   std::unique_ptr<ClassLoaderContext> context = nullptr;
   if (in_classLoaderContext.has_value()) {
-    context = ClassLoaderContext::Create(in_classLoaderContext->c_str());
+    context = ClassLoaderContext::Create(in_classLoaderContext.value());
     if (context == nullptr) {
       return Fatal(
           ART_FORMAT("Class loader context '{}' is invalid", in_classLoaderContext.value()));
@@ -896,7 +896,7 @@
   std::vector<std::unique_ptr<File>> context_files;
   if (context != nullptr) {
     std::vector<std::string> flattened_context = context->FlattenDexPaths();
-    std::string dex_dir = Dirname(in_dexFile.c_str());
+    std::string dex_dir = Dirname(in_dexFile);
     std::vector<int> context_fds;
     for (const std::string& context_element : flattened_context) {
       std::string context_path = std::filesystem::path(dex_dir).append(context_element);
diff --git a/artd/artd_test.cc b/artd/artd_test.cc
index b61b11a..44ddae9 100644
--- a/artd/artd_test.cc
+++ b/artd/artd_test.cc
@@ -72,7 +72,6 @@
 using ::aidl::com::android::server::art::DexoptOptions;
 using ::aidl::com::android::server::art::FileVisibility;
 using ::aidl::com::android::server::art::FsPermission;
-using ::aidl::com::android::server::art::GetDexoptStatusResult;
 using ::aidl::com::android::server::art::IArtdCancellationSignal;
 using ::aidl::com::android::server::art::OutputArtifacts;
 using ::aidl::com::android::server::art::OutputProfile;
@@ -392,7 +391,7 @@
                  std::shared_ptr<IArtdCancellationSignal> cancellation_signal = nullptr) {
     RunDexopt(Property(&ndk::ScopedAStatus::getExceptionCode, expected_status),
               std::move(aidl_return_matcher),
-              cancellation_signal);
+              std::move(cancellation_signal));
   }
 
   void RunDexopt(Matcher<ndk::ScopedAStatus> status_matcher,
diff --git a/artd/path_utils_test.cc b/artd/path_utils_test.cc
index b0cc827..77652f0 100644
--- a/artd/path_utils_test.cc
+++ b/artd/path_utils_test.cc
@@ -28,7 +28,6 @@
 using ::aidl::com::android::server::art::ArtifactsPath;
 using ::aidl::com::android::server::art::DexMetadataPath;
 using ::aidl::com::android::server::art::ProfilePath;
-using ::aidl::com::android::server::art::VdexPath;
 using ::android::base::testing::HasError;
 using ::android::base::testing::HasValue;
 using ::android::base::testing::WithMessage;