gyp: fix post-mortem in v0.11

Expose missing constants and keep symbols on OSX.
Port eba7aae107cb3b482e13b0e88908436fe69a3109 to deps/v8ppc and deps/v8z.
v8: Interrupts must not mask stack overflow.

Backport of https://codereview.chromium.org/339883002
Port 530af9cb8e700e7596b3ec812bad123c9fa06356 to deps/v8ppc and deps/v8z.