Remove ScriptData::PreCompile which takes const char*.

The version taking a Handle should be used instead.

It's not used by Chromium and complicates the ongoing lexer work.

R=svenpanne@chromium.org
BUG=

Review URL: https://codereview.chromium.org/136413003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@18556 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Introduce kGCCallbackForced flag.

This flag will be passed to GC prologue/epilogue callbacks if GC was forced through GC extension.

BUG=
R=dcarney@chromium.org, mstarzinger@chromium.org

Review URL: https://codereview.chromium.org/104023011

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@18558 ce2b1a6d-e550-0410-aec6-3dcde31c8c00