Reviewed by Maciej.

        Implement the callback responsible for handling HTTP headers. This
        callback gets called for every header.
        We will add these headers to our ResourceResponse and on the 'end-of-header'
        indicator we will update the ResourceResponse and dispatch it.

        This patch adds various set methods to ResourceResponse. This improves
        the readability of the headerCallback and avoids storing a CURL handle inside
        the ResourceResponse which would be needed to implement ResourceResponse::doUpdateResourceResponse

        Add a destructor for ResourceHandleManager which would free the resources and remove
        a unused variable.

        * platform/network/ResourceHandleInternal.h:
        (WebCore::ResourceHandleInternal::ResourceHandleInternal):
        * platform/network/ResourceResponse.cpp:
        (WebCore::ResourceResponse::setUrl):
        (WebCore::ResourceResponse::setMimeType):
        (WebCore::ResourceResponse::setExpectedContentLength):
        (WebCore::ResourceResponse::setTextEncodingName):
        (WebCore::ResourceResponse::setSuggestedFilename):
        * platform/network/ResourceResponse.h:
        * platform/network/curl/ResourceHandleCurl.cpp:
        (WebCore::ResourceHandleInternal::~ResourceHandleInternal):
        * platform/network/curl/ResourceHandleManager.cpp:
        (WebCore::ResourceHandleManager::~ResourceHandleManager):
        (WebCore::ResourceHandleManager::sharedInstance):
        (WebCore::headerCallback):
        * platform/network/curl/ResourceHandleManager.h:



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@24372 268f45cc-cd09-0410-ab3c-d52691b4dbfc