Replace basic_string<uint8_t> with std::vector

In newer versions of libc++, std::char_traits<T> is no longer defined
for non-character types, and a result, std::basic_string<uint8_t> is
also no longer defined. See
https://discourse.llvm.org/t/deprecating-std-string-t-for-non-character-t/66779.

Bug: 175635923
Test: make checkbuild
Change-Id: I1893d1b1419f528115739275ca0f1d80ddb22470
diff --git a/media/libaudiohal/impl/DeviceHalAidl.cpp b/media/libaudiohal/impl/DeviceHalAidl.cpp
index fe44ecd..1d8fec0 100644
--- a/media/libaudiohal/impl/DeviceHalAidl.cpp
+++ b/media/libaudiohal/impl/DeviceHalAidl.cpp
@@ -398,8 +398,7 @@
                       *static_cast<StreamCallbackBase*>(this)),
               StreamCallbackBaseHelper<StreamOutHalInterfaceLatencyModeCallback>(
                       *static_cast<StreamCallbackBase*>(this)) {}
-    ndk::ScopedAStatus onCodecFormatChanged(const std::vector<uint8_t>& in_audioMetadata) override {
-        std::basic_string<uint8_t> halMetadata(in_audioMetadata.begin(), in_audioMetadata.end());
+    ndk::ScopedAStatus onCodecFormatChanged(const std::vector<uint8_t>& halMetadata) override {
         return StreamCallbackBaseHelper<StreamOutHalInterfaceEventCallback>::runCb(
                 [&halMetadata](auto cb) { cb->onCodecFormatChanged(halMetadata); });
     }