* Implement virtual buffer copies
* Introduce TranslateAndCreateMultiBuffersPhysicalOnly, use it for copy and clear
* Rename VirtualBufferCache to VirtualRangeCache
* Fix potential issue where virtual range could exist in the cache, without a physical buffer
* Fix bug that could cause copy with negative size on CopyToDependantVirtualBuffer
* Remove virtual copy back for SyncAction
* GetData XML docs
* Make field readonly
* Fix virtual buffer modification tracking
* Remove CopyFromDependantVirtualBuffers from ExternalFlush
* Move things around a little to avoid perf impact
- Inline null check for CopyFromDependantVirtualBuffers
- Remove extra method call for SynchronizeMemoryWithVirtualCopyBack, prefer calling CopyFromDependantVirtualBuffers separately
* Fix up XML doc
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Co-authored-by: riperiperi <rhy3756547@hotmail.com>
