[libFuzzer] Include FuzzedDataProvider.h in the test without "utils" subdir.

[Dor1s]

Summary

This way the test would better match the intended usage of the header,
plus it makes some additional testing (e.g. in CI) a bit easier to set up.

[morehouse]

LGTM

lib/fuzzer/tests/CMakeLists.txt

generate_compiler_rt_tests(FuzzerTestObjects
     SOURCES FuzzerUnittest.cpp ${COMPILER_RT_GTEST_SOURCE}
     RUNTIME ${LIBFUZZER_TEST_RUNTIME}
     DEPS gtest ${LIBFUZZER_TEST_RUNTIME_DEPS} 
     CFLAGS ${LIBFUZZER_UNITTEST_CFLAGS} ${LIBFUZZER_TEST_RUNTIME_CFLAGS}
     LINK_FLAGS ${LIBFUZZER_UNITTEST_LINK_FLAGS} ${LIBFUZZER_TEST_RUNTIME_LINK_FLAGS})
   set_target_properties(FuzzerUnitTests PROPERTIES
     RUNTIME_OUTPUT_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR})
 
+  list(APPEND LIBFUZZER_UNITTEST_CFLAGS -I${COMPILER_RT_SOURCE_DIR}/lib/fuzzer/utils)
+
   set(FuzzedDataProviderTestObjects)
   generate_compiler_rt_tests(FuzzedDataProviderTestObjects
     FuzzedDataProviderUnitTests "FuzzerUtils-${arch}-Test" ${arch}
     SOURCES FuzzedDataProviderUnittest.cpp ${COMPILER_RT_GTEST_SOURCE}
     DEPS gtest ${LIBFUZZER_TEST_RUNTIME_DEPS}
     CFLAGS ${LIBFUZZER_UNITTEST_CFLAGS} ${LIBFUZZER_TEST_RUNTIME_CFLAGS}
     LINK_FLAGS ${LIBFUZZER_UNITTEST_LINK_FLAGS} ${LIBFUZZER_TEST_RUNTIME_LINK_FLAGS})
   set_target_properties(FuzzedDataProviderUnitTests PROPERTIES
     RUNTIME_OUTPUT_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR})
 endif()

lib/fuzzer/tests/FuzzedDataProviderUnittest.cpp

 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 
 #include "gtest/gtest.h"
 #include <cstdint>
 #include <cstdlib>
 
-#include "utils/FuzzedDataProvider.h"
+#include "FuzzedDataProvider.h"
 
 // The test is intentionally extensive, as behavior of |FuzzedDataProvider| must
 // not be broken, given than many fuzz targets depend on it. Changing the
 // behavior might invalidate existing corpora and make the fuzz targets using
 // |FuzzedDataProvider| to lose code coverage accumulated over time.
 
 /* A random 1KB buffer generated by:
 $ python -c "import os; print ',\n'.join([', '.join(['0x%02X' % ord(i) for i \