Remove use of framesToPop from JSTimers
Remove use of framesToPop from JSTimers

Summary:
Replaces the use of `framesToPop` in `_allocateCallback` (in `__DEV__` only) with statically accessing the second frame of the stack.

Changelog: [Internal]

Reviewed By: cpojer

Differential Revision: D17877261

fbshipit-source-id: 8e4d0eb2ed7984b66a99752fb21f7909474fda8f

pandiaraj44/react-native,exponentjs/react-native,javache/react-native,exponent/react-native,hoangpham95/react-native,javache/react-native,pandiaraj44/react-native,javache/react-native,facebook/react-native,janicduplessis/react-native,exponentjs/react-native,pandiaraj44/react-native,myntra/react-native,exponentjs/react-native,hoangpham95/react-native,exponentjs/react-native,javache/react-native,exponent/react-native,arthuralee/react-native,myntra/react-native,janicduplessis/react-native,facebook/react-native,pandiaraj44/react-native,hammerandchisel/react-native,arthuralee/react-native,pandiaraj44/react-native,hoangpham95/react-native,exponentjs/react-native,exponent/react-native,hoangpham95/react-native,exponentjs/react-native,myntra/react-native,myntra/react-native,facebook/react-native,hoangpham95/react-native,myntra/react-native,hoangpham95/react-native,janicduplessis/react-native,javache/react-native,exponent/react-native,javache/react-native,janicduplessis/react-native,pandiaraj44/react-native,myntra/react-native,janicduplessis/react-native,javache/react-native,hoangpham95/react-native,janicduplessis/react-native,exponent/react-native,javache/react-native,hammerandchisel/react-native,facebook/react-native,myntra/react-native,arthuralee/react-native,arthuralee/react-native,exponent/react-native,hammerandchisel/react-native,facebook/react-native,hammerandchisel/react-native,hoangpham95/react-native,exponentjs/react-native,exponent/react-native,pandiaraj44/react-native,exponentjs/react-native,facebook/react-native,myntra/react-native,hammerandchisel/react-native,janicduplessis/react-native,pandiaraj44/react-native,hammerandchisel/react-native,hammerandchisel/react-native,exponent/react-native,facebook/react-native,facebook/react-native,janicduplessis/react-native,facebook/react-native,javache/react-native,myntra/react-native,arthuralee/react-native,hammerandchisel/react-native