Add a basic batch-mode SQL runner for the SAH Pool VFS, for use in comparing it again...

Add a basic batch-mode SQL runner for the SAH Pool VFS, for use in comparing it against WebSQL. Bring the WebSQL batch runner up to date, noting that it cannot run without addition of an "origin trial" activation key from Google because that's now the only way to enable WebSQL in Chrome (that part is not checked in because that key is private). Minor code-adjacent cleanups.

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