Revert of Allow BlobDataHandles to be copied, and have their UUIDs read, on any thread. (https://codereview.chromium.org/259773006/)

Reason for revert:
I'm sorry to revert this change. It looks like it breaks the ASAN bot:

http://build.chromium.org/p/chromium.memory/builders/Linux%20ASan%20LSan%20Tests%20%282%29/builds/2161/steps/content_unittests/logs/ResolveBlobAndCreateUploadDataStream

Direct leak of 120 byte(s) in 3 object(s) allocated from:
    #0 0x520dbb in operator new(unsigned long) /usr/local/google/work/chromium/src/third_party/llvm/projects/compiler-rt/lib/asan/asan_new_delete.cc:62
    #1 0x3a0f611 in webkit_blob::BlobDataHandle::BlobDataHandle(webkit_blob::BlobData*, webkit_blob::BlobStorageContext*, base::SequencedTaskRunner*) webkit/browser/blob/blob_data_handle.cc:42
    #2 0x3a0fd71 in webkit_blob::BlobStorageContext::GetBlobDataFromUUID(std::string const&) webkit/browser/blob/blob_storage_context.cc:69
    #3 0x268955d in ResolveBlobReference content/browser/loader/upload_data_stream_builder.cc:73
...

Original issue's description:
> Allow BlobDataHandles to be copied, and have their UUIDs read, on any thread.
> 
> BUG=108012
> 
> Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=266817
> 
> Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=267423

TBR=michaeln@chromium.org,piman@chromium.org,ericu@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=108012

Review URL: https://codereview.chromium.org/261683005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@267479 0039d316-1c4b-4281-b951-d872f2087c98
5 files changed