Camera NDK: add user context set/get API

Also add ACaptureRequest_copy API.

Test: new NDK CTS test
Bug: 64266031
Change-Id: I77cee16621d92ff3a4cd0c929419a4972b2be040
diff --git a/camera/ndk/impl/ACameraDevice.cpp b/camera/ndk/impl/ACameraDevice.cpp
index 9ce0ac8..45fa28e 100644
--- a/camera/ndk/impl/ACameraDevice.cpp
+++ b/camera/ndk/impl/ACameraDevice.cpp
@@ -372,6 +372,7 @@
     sp<CaptureRequest> req(new CaptureRequest());
     req->mMetadata = request->settings->getInternalData();
     req->mIsReprocess = false; // NDK does not support reprocessing yet
+    req->mContext = request->context;
 
     for (auto outputTarget : request->targets->mOutputs) {
         ANativeWindow* anw = outputTarget.mWindow;
@@ -398,6 +399,7 @@
         ACameraOutputTarget outputTarget(anw);
         pRequest->targets->mOutputs.insert(outputTarget);
     }
+    pRequest->context = req->mContext;
     return pRequest;
 }