lib: remove Object from global's prototype

[bmeck]

Pull Request check-list

Please make sure to review and check all of these items:

• Does make -j8 test (UNIX) or vcbuild test nosign (Windows) pass with
  this change (including linting)?
• Is the commit message formatted according to CONTRIBUTING.md?

Affected core subsystem(s)

lib

Description of change

Removes some strange behavior from having Object in the global object's
prototype chain. No longer introducing global variables coming from
Object.prototype.

These globals have strange warts from existing but we should throw this in CITGM this to see if anything is affected. The only thing I really am suspicious of is toString might be used by some people via type coercion like var_that_refs_global+''.

This would be a breaking change.

[bmeck]

CC: @trevnorris

[Fishrock123]

Wait, we were assigning this again?? Should I be removing this bit in my PR?

[Fishrock123]

This is now done in https://github.com/nodejs/node/pull/5881/files#diff-cc63475f116262e9cbea02374e344c01L211

[jasnell]

Seems reasonable. But let's definitely see what citgm says. /cc @thealphanerd

[Fishrock123]

CI: https://ci.nodejs.org/job/node-test-pull-request/2058/

citgm: https://ci.nodejs.org/job/thealphanerd-smoker/126/

[bmeck]

well the lack of a global toString variable seems to make CITGM blow up

[Slayer95]

Relevant: http://www.ecma-international.org/ecma-262/6.0/index.html#sec-global-object

The value of the [[Prototype]] internal slot of the global object is implementation-dependent.

[bmeck]

@Slayer95 correct, but breaking existing libraries is a bad sign

[Fishrock123]

lodash: fnToString.call(toString)

Oh my. Yeah I'm not sure this will be something we can do. Looks like Chrome also exposes toString(). (and the prototype?)

[Fishrock123]

Maybe we could expose specific ones like toString()?

[bmeck]

@Fishrock123 some people are explicitly checking all known globals by variable name, like in readable-stream/test/common.js and they get reference errors when they don't exist.

[bmeck]

Going to close this after lots of CITGM attempts on my own, too many people using it in the wild.