Reviewed by Sam Weinig.

        - https://bugs.webkit.org/show_bug.cgi?id=21047
          speed up ret_activation with inlining

        About 1% on v8-raytrace.

        * JavaScriptCore.exp: Removed JSVariableObject::setRegisters.

        * kjs/JSActivation.cpp: Moved copyRegisters to the header to make it inline.
        * kjs/JSActivation.h:
        (JSC::JSActivation::copyRegisters): Moved here. Also removed the registerArraySize
        argument to setRegisters, since the object doesn't need to store the number of
        registers.

        * kjs/JSGlobalObject.cpp:
        (JSC::JSGlobalObject::reset): Removed unnecessary clearing left over from when we
        used this on objects that weren't brand new. These days, this function is really
        just part of the constructor.

        * kjs/JSGlobalObject.h: Added registerArraySize to JSGlobalObjectData, since
        JSVariableObjectData no longer needs it. Added a setRegisters override here
        that handles storing the size.

        * kjs/JSStaticScopeObject.h: Removed code to set registerArraySize, since it
        no longer exists.

        * kjs/JSVariableObject.cpp: Moved copyRegisterArray and setRegisters to the
        header to make them inline.
        * kjs/JSVariableObject.h: Removed registerArraySize from JSVariableObjectData,
        since it was only used for the global object.
        (JSC::JSVariableObject::copyRegisterArray): Moved here ot make it inline.
        (JSC::JSVariableObject::setRegisters): Moved here to make it inline. Also
        removed the code to set registerArraySize and changed an if statement into
        an assert to save an unnnecessary branch.



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@36851 268f45cc-cd09-0410-ab3c-d52691b4dbfc