Blink Blobs: Allow creation of WebBlob from just UUID.

Source/web/WebBlob.cpp

Index: Source/web/WebBlob.cpp
diff --git a/Source/web/WebBlob.cpp b/Source/web/WebBlob.cpp
index d27b5bac144d68439bb0a271be4b53c31cfcdf4c..bea9c315fd9e6f8870afde697786711eb7616ba7 100644
--- a/Source/web/WebBlob.cpp
+++ b/Source/web/WebBlob.cpp
@@ -41,6 +41,12 @@ using namespace WebCore;
 
 namespace blink {
 
+WebBlob WebBlob::createFromUUID(const WebString& uuid, const WebString& type, long long size)
+{
+    RefPtrWillBeRawPtr<Blob> blob = Blob::create(BlobDataHandle::create(uuid, type, size));
+    return WebBlob(blob);
+}
+
 WebBlob WebBlob::createFromFile(const WebString& path, long long size)
 {
     OwnPtr<BlobData> blobData = BlobData::create();