Cleanup NNAPI VTS tests

This CL includes the following cleanups:
* namespace compression
* remove "using" from header files
* remove no-op code, default no-op constructors
* clang-formats the code

Bug: N/A
Test: mma
Test: VtsHalNeuralnetworksV1_*TargetTest
Change-Id: I023997d8686ca65223858eed3a0881f5444ed2d6
diff --git a/neuralnetworks/1.2/vts/functional/Callbacks.cpp b/neuralnetworks/1.2/vts/functional/Callbacks.cpp
index a607a08..3972ad6 100644
--- a/neuralnetworks/1.2/vts/functional/Callbacks.cpp
+++ b/neuralnetworks/1.2/vts/functional/Callbacks.cpp
@@ -24,6 +24,8 @@
 
 namespace android::hardware::neuralnetworks::V1_2::implementation {
 
+using V1_0::ErrorStatus;
+
 constexpr Timing kNoTiming = {.timeOnDevice = std::numeric_limits<uint64_t>::max(),
                               .timeInDriver = std::numeric_limits<uint64_t>::max()};