x/tools/go/gcexportdata: simplify implementation assuming go >= 1.21

[timothy-king]

This is a tracking issue to simplify the implementation of x/tools/{go/gcexportdata,internal/gcimporter} since the acceptance of proposal #68898. These can now assume exportdata only comes from go versions >= 1.21.

[gabyhelp]

Related Issues

• x/tools/go/gcimporter: update export data format version #17734 (closed)

_{(Emoji vote if this was helpful or unhelpful; more detailed feedback welcome in this discussion.)}

[gopherbot]

Change https://go.dev/cl/633115 mentions this issue: internal/gcimporter: require archive files

[gopherbot]

Change https://go.dev/cl/633279 mentions this issue: internal/gcimporter: require binary export data header

[gopherbot]

Change https://go.dev/cl/633278 mentions this issue: internal/gcimporter: update FindExportData to return a non-negative size

[gopherbot]

Change https://go.dev/cl/633296 mentions this issue: internal/gcimporter: remove end-of-section marker from size

[gopherbot]

Change https://go.dev/cl/633435 mentions this issue: internal/gcimporter: remove indexed support from Import

[gopherbot]

Change https://go.dev/cl/633708 mentions this issue: internal/gcimporter: require archive files

[gopherbot]

Change https://go.dev/cl/633716 mentions this issue: internal/gcimporter: require binary export data header

[gopherbot]

Change https://go.dev/cl/633712 mentions this issue: internal/gcimporter: update FindExportData to return a non-negative size