Make environment_variables test ignore LD_LIBRARY_PATH for glibc
Make environment_variables test ignore LD_LIBRARY_PATH for glibc

This test pumps specific values through sel_ldr with -E and then
tests that the entire environment seen by the untrusted program
is exactly that list, using a golden file.  CommandSelLdrTestNacl
uses -E to pass LD_LIBRARY_PATH to the nexe for new (ARM) glibc.
So that variable's presence in environ is not a bug.

BUG= https://code.google.com/p/nativeclient/issues/detail?id=3068
TEST= trybots + scons platform=arm --nacl_glibc run_env_var_test_irt
R=phosek@chromium.org, mseaborn@chromium.org

Review URL: https://codereview.chromium.org/1116963005

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