2014-08-04  Sharath Kamath  <s.kamath@samsung.com>

        Enable the KHR_FP64 & KHR_FP16 extension.

        Issue #536 - [Part-1]

        Reviewed by NOBODY (OOPS!).

        Pushing the extension availability to OpenCL, and enabling only when
        the OpenCL lists the extensions name "cl_khr_fp64" & "cl_khr_fp16" in the device & platform
        getInfo() calls.

        * platform/opencl/ComputeExtensionsCL.cpp:
        (WebCore::ComputeExtensions::supportsExtension):
2014-08-04  Sharath Kamath  <s.kamath@samsung.com>

        Enable the KHR_FP64 extension.

        In OpenCL1.2 only when CL_DEVICE_DOUBLE_FP_CONFIG is non-null the
        implementation supports double data type.
        Adopting the same in cacheExtensionsForDevice() to cache KHR_FP64 support.
        Also cacheExtensionsForPlatform() must check for support to KHR_FP64 in all the devices
        and then cache the extensions status.

        Issue #536 - [Part-2]

        Reviewed by NOBODY (OOPS!).

        * platform/ComputeExtensions.h:
        * platform/ComputePlatform.h:
        * platform/opencl/ComputeExtensionsCL.cpp:
        (WebCore::ComputeExtensions::supports):
        (WebCore::ComputeExtensions::cacheGlobalExtensions):
        (WebCore::ComputeExtensions::cacheExtensionsForDevice):
        (WebCore::ComputeExtensions::cacheExtensionsForPlatform):
        * platform/opencl/ComputePlatformCL.cpp:
        (WebCore::ComputePlatform::getPlatformInfo):