TBR: i#2122: fix out-of-bounds reads in os_page_size_init()

Commit log for first patchset:
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i#2122: fix out-of-bounds reads in os_page_size_init()

Disables the beyond-environ reads in os_page_size_init() for STATIC_LIBRARY
where they are likely to not be on the stack and instead read off into
unallocated memory.

Fixes #2122
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[bruening, 2017-01-06 02:41:36]

Committed as
https://github.com/DynamoRIO/dynamorio/commit/3360fee852accd08ebb9ba08813cb33...

Final commit log: 
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i#2122: fix out-of-bounds reads in os_page_size_init()

Disables the beyond-environ reads in os_page_size_init() for STATIC_LIBRARY
where they are likely to not be on the stack and instead read off into
unallocated memory.

Fixes #2122

Review-URL: https://codereview.appspot.com/319080043
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