Fix memory leak in nativeDecodeFileDescriptor

Fix memory leak in nativeDecodeFileDescriptor:
SkFILEStream::kCallerRetains_Ownership is used to keep
life cycle of file in Java,so fclose is not called when
destruct SkFILEStream because ownership not belong to
native here, while when file is closed in Java, close
is called instead of fclose,that means buffer allocated
by malloc in fseek, when create SkFrontBufferedStream
with this filestream, will not be freed, because this
buffer will only be freedin fclose.
To fix this issue: duplicate this fd, and use
SkFILEStream::kCallerPasses_Ownership for SkFILEStream,
means Java and native manage file life cycle separately.
CRs-Fixed: 718738

Change-Id: I1c664551ab8d381db2e1f948a2207bc6fb7a11f9