fbcode: remove unused includes from .cpp files with no #if and #define

Summary:
This is a first diff to remove the "easiest" unused includes in fbcode.

* For safety, we only touch .cpp files without #if and #define,
* We do not try to remove redundant systems headers (aka. "packing").

The diff was generated as follows:
```
foundation/scripts/ls-cpp-dirs | grep -v '^\(\.\.\|external/\|.*/external\)' | xargs ffmr -o /tmp/ffmr-diff-1 codegraph/scripts/ffmr/analyze_includes_no_headers_no_packing_skipping_ifdefs.sh

cat /tmp/ffmr-diff-1/*.diff | patch -p2
hg commit -m something
arc diff --prepare --nolint --nounit --less-context --excuse refactoring
```

Note: `grep -v` is just an optimization. The actual configuration is in these two files:
diffusion/FBS/browse/master/fbcode/codegraph/analysis/config.py
diffusion/FBS/browse/master/fbcode/codegraph/scripts/ffmr/analyze_includes_no_headers_no_packing_skipping_ifdefs.sh

See the task for more context, and the recent "safety" improvements on the tool.

depends on D4317825 for very few cases where `nolint` had to be manually added.

Reviewed By: igorsugak

Differential Revision: D4312617

fbshipit-source-id: ecc1f0addfd0651fa4770fcc43cd1314661a311a

folly/experimental/RCUUtils.cpp

@@ -15,10 +15,8 @@
  */
 #include <folly/experimental/RCUUtils.h>
 
-#include <folly/Portability.h>
 #include <folly/ThreadLocal.h>
 
-
 namespace folly {
 
 namespace {

folly/experimental/exception_tracer/test/ExceptionCounterTest.cpp

@@ -15,7 +15,6 @@
  */
 
 #include <stdexcept>
-#include <typeinfo>
 #include <thread>
 #include <mutex>
 #include <condition_variable>

folly/experimental/io/FsUtil.cpp

@@ -17,7 +17,6 @@
 #include <folly/experimental/io/FsUtil.h>
 
 #include <folly/Exception.h>
-#include <folly/portability/Unistd.h>
 
 namespace bsys = ::boost::system;
 

folly/experimental/io/HugePageUtil.cpp

@@ -14,25 +14,16 @@
  * limitations under the License.
  */
 
-#include <sys/mman.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <errno.h>
-#include <fcntl.h>
-
 #include <iostream>
 #include <stdexcept>
-#include <system_error>
 
 #include <folly/File.h>
 #include <folly/Format.h>
 #include <folly/MemoryMapping.h>
-#include <folly/Portability.h>
 #include <folly/Range.h>
 #include <folly/ScopeGuard.h>
 #include <folly/experimental/io/HugePages.h>
 #include <folly/portability/GFlags.h>
-#include <folly/portability/Unistd.h>
 
 DEFINE_bool(cp, false, "Copy file");
 

folly/experimental/test/TestUtilTest.cpp

@@ -16,7 +16,6 @@
 
 #include <folly/experimental/TestUtil.h>
 
-#include <sys/stat.h>
 #include <sys/types.h>
 
 #include <system_error>

folly/futures/ManualExecutor.cpp

@@ -20,8 +20,6 @@
 #include <string>
 #include <tuple>
 
-#include <stdexcept>
-
 namespace folly {
 
 void ManualExecutor::add(Func callback) {

folly/futures/test/RetryingTest.cpp

@@ -16,13 +16,11 @@
 
 #include <algorithm>
 #include <atomic>
-#include <exception>
 #include <vector>
 
 #include <folly/futures/Future.h>
 #include <folly/portability/GTest.h>
 
-
 using namespace std;
 using namespace std::chrono;
 using namespace folly;

folly/futures/test/TimekeeperTest.cpp

@@ -16,7 +16,6 @@
 
 #include <folly/futures/Timekeeper.h>
 #include <folly/portability/GTest.h>
-#include <folly/portability/Unistd.h>
 
 using namespace folly;
 using std::chrono::milliseconds;

folly/io/ShutdownSocketSet.cpp

@@ -16,8 +16,6 @@
 
 #include <folly/io/ShutdownSocketSet.h>
 
-#include <sys/types.h>
-
 #include <chrono>
 #include <thread>
 

folly/io/async/test/DelayedDestructionBaseTest.cpp

@@ -34,8 +34,6 @@
 #include <folly/io/async/DelayedDestructionBase.h>
 
 #include <functional>
-#include <list>
-#include <vector>
 
 #include <folly/portability/GTest.h>
 

folly/io/async/test/HHWheelTimerTest.cpp

@@ -22,8 +22,6 @@
 #include <folly/io/async/test/Util.h>
 #include <folly/portability/GTest.h>
 
-#include <vector>
-
 using namespace folly;
 using std::chrono::milliseconds;
 

folly/io/async/test/SSLSessionTest.cpp

@@ -17,7 +17,6 @@
 #include <folly/io/async/test/AsyncSSLSocketTest.h>
 #include <folly/portability/GTest.h>
 #include <folly/portability/Sockets.h>
-#include <folly/portability/Unistd.h>
 #include <folly/ssl/SSLSession.h>
 
 using namespace std;

folly/io/async/test/SocketPair.cpp

@@ -24,7 +24,6 @@
 #include <folly/portability/Unistd.h>
 
 #include <errno.h>
-#include <sys/types.h>
 #include <stdexcept>
 
 namespace folly {

folly/test/AtomicHashMapTest.cpp

@@ -24,7 +24,6 @@
 #include <folly/Assume.h>
 #include <folly/Benchmark.h>
 #include <folly/Conv.h>
-#include <folly/portability/Atomic.h>
 #include <folly/portability/GTest.h>
 #include <folly/portability/SysTime.h>
 

folly/test/BatonTest.cpp

@@ -20,7 +20,6 @@
 #include <folly/portability/GTest.h>
 
 #include <thread>
-#include <semaphore.h>
 
 using namespace folly;
 using namespace folly::test;

folly/test/ExceptionWrapperTest.cpp

@@ -18,7 +18,6 @@
 
 #include <folly/ExceptionWrapper.h>
 #include <folly/Conv.h>
-#include <folly/Portability.h>
 #include <folly/portability/GTest.h>
 
 using namespace folly;

folly/test/LoggingBenchmark.cpp

@@ -18,8 +18,6 @@
 
 #include <folly/Benchmark.h>
 
-#include <vector>
-
 BENCHMARK(skip_overhead, iter) {
   auto prev = FLAGS_minloglevel;
   FLAGS_minloglevel = 2;

folly/test/MemoryIdlerTest.cpp

@@ -19,12 +19,9 @@
 #include <folly/Baton.h>
 #include <folly/portability/GMock.h>
 #include <folly/portability/GTest.h>
-#include <folly/portability/Windows.h>
 
 #include <memory>
 #include <thread>
-#include <assert.h>
-#include <semaphore.h>
 
 using namespace folly;
 using namespace folly::detail;

folly/test/PortabilityTest.cpp

@@ -14,8 +14,6 @@
  * limitations under the License.
  */
 
-#include <folly/Portability.h>
-
 #include <memory>
 
 #include <folly/portability/GTest.h>

folly/test/RandomBenchmark.cpp

@@ -22,9 +22,7 @@
 
 #include <glog/logging.h>
 
-#include <algorithm>
 #include <thread>
-#include <vector>
 #include <random>
 
 using namespace folly;

folly/test/ScopeGuardTest.cpp

@@ -15,7 +15,6 @@
  */
 
 #include <folly/ScopeGuard.h>
-#include <folly/Portability.h>
 
 #include <glog/logging.h>
 

folly/test/SingletonTestGlobal.cpp

@@ -22,8 +22,6 @@
 #include <folly/test/SingletonTestStructs.h>
 #include <folly/portability/GTest.h>
 
-#include <glog/logging.h>
-
 /*
  * This test needs to be in its own file, as a standalone program.
  * We want to ensure no other singletons are registered, so we can

folly/test/SingletonVaultCTest.cpp

@@ -17,8 +17,6 @@
 #include <folly/Singleton.h>
 #include <folly/SingletonVault_c.h>
 
-#include <thread>
-
 #include <folly/portability/GTest.h>
 
 FOLLY_TLS long instance_counter_instances = 0;

folly/test/StringBenchmark.cpp

@@ -19,7 +19,6 @@
 #include <boost/algorithm/string.hpp>
 #include <folly/Benchmark.h>
 #include <folly/Random.h>
-#include <cstdarg>
 #include <random>
 
 using namespace folly;

folly/test/SubprocessTestParentDeathHelper.cpp

@@ -23,7 +23,6 @@
 // worked as intended.
 
 #include <sys/types.h>
-#include <sys/stat.h>
 #include <fcntl.h>
 #include <signal.h>
 

folly/test/ThreadLocalTestLib.cpp

@@ -13,8 +13,6 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-#include <iostream>
-#include <thread>
 
 #include <folly/ThreadLocal.h>