Now also fixes: https://github.com/flutter/flutter/issues/153737
Being able to reorder rendering commands leads to optimization opportunities in the graphics package. A graphics package being fed from a DisplayList either has to take the commands in the order given or implement their own storage format for the rendering data.
With this new dispatching mechanism, the graphics package can both query basic information about the recorded ops and even dispatch them by the index into the list. Query information includes either the "category" of the op (clip/transform/render, etc.) or a specific op type enum. The package can dispatch some categories (or ops) immediately and remember other categories (or ops) along with their state for dispatching later.
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