Chromium Paint Records and Deferred Image Pipelines

The sources describe DeferredPaintRecord as a specialized mechanism within the Chromium engine used to handle image-like content that is not yet ready for rendering. Unlike a PaintRecord, which contains a fully realized list of drawing commands, a DeferredPaintRecord acts as a placeholder or "input" that is resolved into actual pixels or commands later in the pipeline. It is primarily managed within a PaintImage and is commonly used for complex features like CSS Paint Worklets or deferred canvas drawings. Standard image operations like DrawImageOp and DrawImageRectOp serve as the transport for these objects, detecting their presence and triggering resolution during the rasterization phase. While both DrawRecordOp and deferred images are flattened into standard operations during serialization, they represent distinct stages of the rendering process. Ultimately, the system treats these deferred records as "late-binding" image payloads to allow for asynchronous work and more flexible memory management.