Remove a horrible hack aiming at Ubuntu 14.04's libstdc++_pic.

Because our supported build environments no longer include Ubuntu 14.04,
and this is causing problems with libc++-based builds.

flow/Platform.cpp

@@ -2843,28 +2843,6 @@ void setupSlowTaskProfiler() {
 #endif
 }
 
-#ifdef __linux__
-// There's no good place to put this, so it's here.
-// Ubuntu's packaging of libstdc++_pic offers different symbols than libstdc++.  Go figure.
-// Notably, it's missing a definition of std::istream::ignore(long), which causes compilation errors
-// in the bindings.  Thus, we provide weak versions of their definitions, so that if the
-// linked-against libstdc++ is missing their definitions, we'll be able to use the provided
-// ignore(long, int) version.
-#include <istream>
-namespace std {
-typedef basic_istream<char, std::char_traits<char>> char_basic_istream;
-template <>
-char_basic_istream& __attribute__((weak)) char_basic_istream::ignore(streamsize count) {
-  return ignore(count, std::char_traits<char>::eof());
-}
-typedef basic_istream<wchar_t, std::char_traits<wchar_t>> wchar_basic_istream;
-template <>
-wchar_basic_istream& __attribute__((weak)) wchar_basic_istream::ignore(streamsize count) {
-  return ignore(count, std::char_traits<wchar_t>::eof());
-}
-}
-#endif
-
 // UnitTest for getMemoryInfo
 #ifdef __linux__
 TEST_CASE("/flow/Platform/getMemoryInfo") {