libcef.so is huge (500 MB) in Chrome v54+

[cztomczak]

Reported on the CEF Forum: https://magpcss.org/ceforum/viewtopic.php?f=6&t=14595

Related upstream CEF issue: https://bitbucket.org/chromiumembedded/cef/issues/1979/linux-determine-strategy-for-stripping

SOLUTION (temporary): currently the only option is to strip all symbols from libcef.so using Linux strip command. This reduces size to 100 MB. However with this you won't be able to get any meaningful stack trace when debugging with gdb. This huge size of libcef.so was caused by move from GYP to GN. This might be resolved in the future.

Implications:

1. Distribution packages on PyPI and on GH Releases will have symbols stripped to get the best size of the package (50 MB).
2. If you need libcef.so with minimal symbols so that you can debug with gdb and get a meaningful stack trace (see the InternalDevelopment wiki page), then download Upstream CEF binaries and libraries from GH releases tagged "v54-upstream". This package (150 MB) contains the original 500 MB libcef.so built with GN's symbol_level=1.

Related issue: #260 (Update to Chrome v54).