Remove BlobRegistry indirection since there is only one implementation.

BUG=

Review URL: https://chromiumcodereview.appspot.com/15851008

git-svn-id: svn://svn.chromium.org/blink/trunk@152746 bbb929c8-8fbe-4397-9dbb-9b2b20218538
void BlobRegistryProxy::addDataToStream(const KURL& url, PassRefPtr<RawData> streamData)
{
    if (m_webBlobRegistry) {
        WebKit::WebThreadSafeData webThreadSafeData(streamData);
        m_webBlobRegistry->addDataToStream(url, webThreadSafeData);
    }
}

void BlobRegistryProxy::addDataToStream(const KURL& url, PassRefPtr<RawData> streamData)
{
    if (m_webBlobRegistry) {
        WebKit::WebThreadSafeData webThreadSafeData(streamData);
        m_webBlobRegistry->addDataToStream(url, webThreadSafeData);
    }
}
