Implement Blob.close().

Source/core/fileapi/Blob.cpp

Index: Source/core/fileapi/Blob.cpp
diff --git a/Source/core/fileapi/Blob.cpp b/Source/core/fileapi/Blob.cpp
index 4fa8e1f947b7f35a4758164e9c749141686ff264..ddca8af746aef8afc4a1dcdb19c1dbfa3de18c9e 100644
--- a/Source/core/fileapi/Blob.cpp
+++ b/Source/core/fileapi/Blob.cpp
@@ -31,6 +31,8 @@
 #include "config.h"
 #include "core/fileapi/Blob.h"
 
+#include "core/dom/DOMURL.h"
+#include "core/dom/ExecutionContext.h"
 #include "platform/blob/BlobRegistry.h"
 #include "platform/blob/BlobURL.h"
 
@@ -46,10 +48,11 @@ public:
     static URLRegistry& registry();
 };
 
-void BlobURLRegistry::registerURL(SecurityOrigin* origin, const KURL& publicURL, URLRegistrable* blob)
+void BlobURLRegistry::registerURL(SecurityOrigin* origin, const KURL& publicURL, URLRegistrable* registrableObject)
 {
-    ASSERT(&blob->registry() == this);
-    BlobRegistry::registerPublicBlobURL(origin, publicURL, static_cast<Blob*>(blob)->blobDataHandle());
+    ASSERT(&registrableObject->registry() == this);
+    Blob* blob = static_cast<Blob*>(registrableObject);
+    BlobRegistry::registerPublicBlobURL(origin, publicURL, blob->blobDataHandle());
 }
 
 void BlobURLRegistry::unregisterURL(const KURL& publicURL)
@@ -67,6 +70,7 @@ URLRegistry& BlobURLRegistry::registry()
 
 Blob::Blob(PassRefPtr<BlobDataHandle> dataHandle)
     : m_blobDataHandle(dataHandle)
+    , m_hasBeenClosed(false)
 {
     ScriptWrappable::init(this);
 }
@@ -111,6 +115,25 @@ PassRefPtr<Blob> Blob::slice(long long start, long long end, const String& conte
     return Blob::create(BlobDataHandle::create(blobData.release(), length));
 }
 
+void Blob::close(ExecutionContext* executionContext)
+{
+    if (!hasBeenClosed()) {
+        // Dereferencing a Blob that has been closed should result in
+        // a network error. Revoke URLs registered against it through
+        // its UUID.
+        DOMURL::revokeObjectUUID(executionContext, uuid());
+
+        // A closed Blob should have size zero, which most consumers
+        // will treat as an empty Blob. The exception being the FileReader
+        // read operations which will throw.
+        // FIXME: spec not yet set in stone in this regard, track updates to it (http://crbug.com/344820.)
+        OwnPtr<BlobData> blobData = BlobData::create();
+        blobData->setContentType(type());
+        m_blobDataHandle = BlobDataHandle::create(blobData.release(), 0);
+        m_hasBeenClosed = true;
+    }
+}
+
 void Blob::appendTo(BlobData& blobData) const
 {
     blobData.appendBlob(m_blobDataHandle, 0, m_blobDataHandle->size());
@@ -121,5 +144,4 @@ URLRegistry& Blob::registry() const
     return BlobURLRegistry::registry();
 }
 
-
 } // namespace WebCore