2014-04-03  Gajendra N  <gajendra.n@samsung.com>

        Support WebCLKernel::setArg(index, <64bit-integer>)

        Issue #461

        Reviewed by Antonio.

        WebCL spec says 64-bit integers must be represented as pairs of 32-bit
        unsigned integers. The low-order 32 bits are stored in the first element of
        each pair, and the high-order 32 bits in the second element. As little endian
        architecture follows the same format, it is automatically taken care of. For
        Big endian architecture, order for 32 bit uint elements need to be swapped
        before passing to OpenCL.

        Swapping low and high order 32bit data before passing to kernels that accepts
        ulong input, for Big Endian Architecture.

        * Modules/webcl/WebCLKernel.cpp:
        (WebCore::WebCLKernel::setArg):