Bug 1533133 - Fix missing linker and JS engine options for SSP. r=glandium

Differential Revision: https://phabricator.services.mozilla.com/D22730

--HG--
extra : moz-landing-system : lando

build/moz.configure/toolchain.configure

@@ -1617,6 +1617,9 @@ def security_hardening_cflags(hardening_flag, asan, optimize, c_compiler, target
             # mingw-clang cross-compile toolchain has bugs with stack protector
             if target.os != 'WINNT' or c_compiler == 'gcc':
                 flags.append("-fstack-protector-strong")
+                ldflags.append("-fstack-protector-strong")
+                js_flags.append("-fstack-protector-strong")
+                js_ldflags.append("-fstack-protector-strong")
 
         # ASLR ------------------------------------------------
         # ASLR (dynamicbase) is enabled by default in clang-cl; but the