Add dependency to gflags and related tests

[wangkuiyi]

Fixes #822

[wangkuiyi]

The current problem is that the building of glog errors:

ERROR: /paddle/third_party/glog_test/BUILD:3:1: Linking of rule '//third_party/glog_test:glog_test' failed: process-wrapper failed: error executing command /root/.cache/bazel/_bazel_root/8c87e0642c6bf396d03eecdb205876e7/execroot/paddle/_bin/process-wrapper -1 5 - - /usr/bin/gcc -o bazel-out/local-fastbuild/bin/third_party/glog_test/glog_test ... (remaining 11 argument(s) skipped).
bazel-out/local-fastbuild/bin/_solib_k8/libexternal_Sglog_Slibglog.so: undefined reference to `google::FlagRegisterer::FlagRegisterer(char const*, char const*, char const*, char const*, void*, void*)'

The problem is that the symbol FlagRegisterer was defined in namespace gflags other than google as glog expected:

root@0c34bd561238:/paddle# nm -gC bazel-out/local-fastbuild/bin/_solib_k8/libexternal_Sgflags_Slibgflags.so | grep -i FlagRegisterer
0000000000024930 W gflags::FlagRegisterer::FlagRegisterer<std::string>(char const*, char const*, char const*, std::string*, std::string*)
0000000000025180 W gflags::FlagRegisterer::FlagRegisterer<bool>(char const*, char const*, char const*, bool*, bool*)
000000000002545a W gflags::FlagRegisterer::FlagRegisterer<double>(char const*, char const*, char const*, double*, double*)
0000000000025212 W gflags::FlagRegisterer::FlagRegisterer<int>(char const*, char const*, char const*, int*, int*)
00000000000252a4 W gflags::FlagRegisterer::FlagRegisterer<unsigned int>(char const*, char const*, char const*, unsigned int*, unsigned int*)
0000000000025336 W gflags::FlagRegisterer::FlagRegisterer<long>(char const*, char const*, char const*, long*, long*)
00000000000253c8 W gflags::FlagRegisterer::FlagRegisterer<unsigned long>(char const*, char const*, char const*, unsigned long*, unsigned long*)
0000000000024930 W gflags::FlagRegisterer::FlagRegisterer<std::string>(char const*, char const*, char const*, std::string*, std::string*)
0000000000025180 W gflags::FlagRegisterer::FlagRegisterer<bool>(char const*, char const*, char const*, bool*, bool*)
000000000002545a W gflags::FlagRegisterer::FlagRegisterer<double>(char const*, char const*, char const*, double*, double*)
0000000000025212 W gflags::FlagRegisterer::FlagRegisterer<int>(char const*, char const*, char const*, int*, int*)
00000000000252a4 W gflags::FlagRegisterer::FlagRegisterer<unsigned int>(char const*, char const*, char const*, unsigned int*, unsigned int*)
0000000000025336 W gflags::FlagRegisterer::FlagRegisterer<long>(char const*, char const*, char const*, long*, long*)
00000000000253c8 W gflags::FlagRegisterer::FlagRegisterer<unsigned long>(char const*, char const*, char const*, unsigned long*, unsigned long*)

The root of the reason is that the BUILD file in gflags repo uses gflags as the default C++ namespace name https://github.com/gflags/gflags/blob/v2.2.0/BUILD#L10. My fix is to provide my own gflags.BUILD which uses google as the default namespace.

[reyoung]

LGTM

[reyoung]

这个文件目前还有点问题，参考这个PR #873

所以，麻烦把这个文件revert吧。

[wangkuiyi]

我一revert就过不了pre-commit check了。

这里把 #include "hl_cuda.h" 这行挪一下位置应该不会影响编译才对？

[reyoung]

不影响编译，影响了clang-format的自动化format。。

因为似乎clang-format 4.X 和3.8+在这个细节上有区别。

[reyoung]

要不先等#873 merge就好了。。手动把这段format关掉就行了。。

或者在您这个PR里面手动关掉。我把我那个PR close掉也行

[wangkuiyi]

Done