2014-01-09  Sharath Kamath  <s.kamath@samsung.com>

        Need to validate buffers/images sent belong to same context.

        Issue #395

        Reviewed by Antonio.

        Currently all context match for buffers/images with queus is
        done by OpenCL. Since it will create a dependency on OpenCL it is not recommended.

        Instead of passing the context verification downt to OpenCL,
        checking it at WebCL to ensure the context cached in queue is same as
        that of the buffers sent to enqueue* API's.

        No new tests.

        * Modules/webcl/WebCLCommandQueue.cpp:
        (WebCore::WebCLCommandQueue::isValidContext):
        (WebCore::WebCLCommandQueue::enqueueWriteBufferBase):
        (WebCore::WebCLCommandQueue::enqueueWriteBufferRectBase):
        (WebCore::WebCLCommandQueue::enqueueReadBufferBase):
        (WebCore::WebCLCommandQueue::enqueueReadImageBase):
        (WebCore::WebCLCommandQueue::enqueueReadBufferRectBase):
        (WebCore::WebCLCommandQueue::enqueueWriteImageBase):
        (WebCore::WebCLCommandQueue::enqueueCopyImage):
        (WebCore::WebCLCommandQueue::enqueueCopyImageToBuffer):
        (WebCore::WebCLCommandQueue::enqueueCopyBufferToImage):
        (WebCore::WebCLCommandQueue::enqueueCopyBuffer):
        (WebCore::WebCLCommandQueue::enqueueCopyBufferRect):
        * Modules/webcl/WebCLCommandQueue.h:
        * Modules/webcl/WebCLMemoryObject.h:
        (WebCore::WebCLMemoryObject::associatedContext):