[Win] JavaScript crashes on 64-bit with JIT enabled.
https://bugs.webkit.org/show_bug.cgi?id=124409

Patch by peavo@outlook.com <peavo@outlook.com> on 2013-11-15
Reviewed by Michael Saboff.

These are issues found with JIT on 64-bit:
- The registers rsi and rdi in callToJavaScript needs to be saved and restored. This is required by the Windows 64-bit ABI.
- The getHostCallReturnValue function needs to be updated according to it's GCC counterpart.
- The poke argument offset needs to be 20h, because Windows 64-bit ABI requires stack space allocated for the 4 argument registers.

* JavaScriptCore.vcxproj/JavaScriptCore.vcxproj: Re-added JITStubsMSVC64.asm to project.
* jit/CCallHelpers.h: Set poke argument offset.
(JSC::CCallHelpers::setupArguments): Compile fix, added needed method.
* jit/JITStubsMSVC64.asm: Save and restore registers rsi and rdi.
                          Update getHostCallReturnValue according to the GCC version.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@159376 268f45cc-cd09-0410-ab3c-d52691b4dbfc