Build error in Ubuntu18.04

[BunnyRabbit8mile]

[ 34%] Building CXX object CMakeFiles/TokenBindingConstructorTest.dir/extensions/tokenbinding/test/TokenBindingConstructorTest.cpp.o
/home/stanlee/Opensource/proxygen/proxygen/fizz/fizz/tool/Main.cpp:18:15: error: expected constructor, destructor, or type conversion before ‘(’ token
DECLARE_string(vmodule);
^
/home/stanlee/Opensource/proxygen/proxygen/fizz/fizz/tool/Main.cpp: In function ‘void parseVerbosityFlags(const std::vector<std::__cxx11::basic_string >&)’:
/home/stanlee/Opensource/proxygen/proxygen/fizz/fizz/tool/Main.cpp:45:7: error: ‘FLAGS_vmodule’ was not declared in this scope
FLAGS_vmodule = arguments[i + 1];
^~~~~~~~~~~~~
CMakeFiles/FizzTool.dir/build.make:62: recipe for target 'CMakeFiles/FizzTool.dir/tool/Main.cpp.o' failed
make[2]: *** [CMakeFiles/FizzTool.dir/tool/Main.cpp.o] Error 1
CMakeFiles/Makefile2:67: recipe for target 'CMakeFiles/FizzTool.dir/all' failed
make[1]: *** [CMakeFiles/FizzTool.dir/all] Error 2

When I install the proxygen on my Ubuntu18.04 computer(gcc version 8.2), I met this issue.And I found that DECLARE_string() was defined at folly/folly/portability/GFlags.h header file, this header file was not include in fizz/fizz/tool/Main.cpp. So I locally fixed this issue by adding #include <folly/portability/GFlags.h> in Main.cpp.

[knekritz]

Fixed in eaf86f0.