Consolidate NNAPI VTS utility code

This CL does additional NNAPI VTS test cleanup, including consolidating
duplicate functionality. Specifically, this CL:
* consolidates the createPreparedModel function, removing the duplicate
* consolidates the std::out ErrorStatus and DeviceStatus code into Utils
* changes non-null constant pointers to constant references
* removes redudant leading namespace specifiers (V1_0::, ::testing, etc.)
* makes the Valdiation tests free functions
* renames device to kDevice and mTestModel to kTestModel

Bug: N/A
Test: mma
Test: VtsHalNeuralnetworksV1_*TargetTest (with sample-all)
Change-Id: Ic401bb1f1760cc10384ac0d30c0c93409b63a9c7
Merged-In: Ic401bb1f1760cc10384ac0d30c0c93409b63a9c7
(cherry picked from commit e16af0a44ba9b76667a598b10a085f808efb8c7c)
diff --git a/neuralnetworks/1.2/vts/functional/GeneratedTestHarness.h b/neuralnetworks/1.2/vts/functional/GeneratedTestHarness.h
index cb01b91..0b8b917 100644
--- a/neuralnetworks/1.2/vts/functional/GeneratedTestHarness.h
+++ b/neuralnetworks/1.2/vts/functional/GeneratedTestHarness.h
@@ -29,36 +29,20 @@
 
 class GeneratedTestBase
     : public NeuralnetworksHidlTest,
-      public ::testing::WithParamInterface<test_helper::TestModelManager::TestParam> {
+      public testing::WithParamInterface<test_helper::TestModelManager::TestParam> {
   protected:
-    void SetUp() override {
-        NeuralnetworksHidlTest::SetUp();
-        ASSERT_NE(mTestModel, nullptr);
-    }
-
-    const test_helper::TestModel* mTestModel = GetParam().second;
+    const test_helper::TestModel& kTestModel = *GetParam().second;
 };
 
-#define INSTANTIATE_GENERATED_TEST(TestSuite, filter)                                          \
-    INSTANTIATE_TEST_SUITE_P(                                                                  \
-            TestGenerated, TestSuite,                                                          \
-            ::testing::ValuesIn(::test_helper::TestModelManager::get().getTestModels(filter)), \
+#define INSTANTIATE_GENERATED_TEST(TestSuite, filter)                                        \
+    INSTANTIATE_TEST_SUITE_P(                                                                \
+            TestGenerated, TestSuite,                                                        \
+            testing::ValuesIn(::test_helper::TestModelManager::get().getTestModels(filter)), \
             [](const auto& info) { return info.param.first; })
 
 // Tag for the validation tests, instantiated in VtsHalNeuralnetworks.cpp.
 // TODO: Clean up the hierarchy for ValidationTest.
-class ValidationTest : public GeneratedTestBase {
-  protected:
-    void validateEverything(const Model& model, const V1_0::Request& request);
-    void validateFailure(const Model& model, const V1_0::Request& request);
-
-  private:
-    void validateModel(const Model& model);
-    void validateRequest(const sp<IPreparedModel>& preparedModel, const V1_0::Request& request);
-    void validateRequestFailure(const sp<IPreparedModel>& preparedModel,
-                                const V1_0::Request& request);
-    void validateBurst(const sp<IPreparedModel>& preparedModel, const V1_0::Request& request);
-};
+class ValidationTest : public GeneratedTestBase {};
 
 Model createModel(const ::test_helper::TestModel& testModel);