Jonah Williams f64d4f6eb7 [Impeller] Switch back to using explicit flush for device buffers. (flutter/engine#43644) ...

Not all devices support the host_coherent + host_visible + device_local combo (though most do). I believe this change was associated with a slight regression in performance, so back it out and go back to flush to see if that improves things.

https://flutter-flutter-perf.skia.org/e/?begin=1687535096&end=1689267073&queries=device_type%3DSM-G973U1%26test%3Dnew_gallery_impeller__transition_perf&requestType=0&selected=commit%3D35596%26name%3D%252Carch%253Dintel%252Cbranch%253Dmaster%252Cconfig%253Ddefault%252Cdevice_type%253DSM-G973U1%252Cdevice_version%253Dnone%252Chost_type%253Dlinux%252Csub_result%253D99th_percentile_frame_rasterizer_time_millis%252Ctest%253Dnew_gallery_impeller__transition_perf%252C

Specifically:

![image](https://github.com/flutter/engine/assets/8975114/fedabc18-9091-45c0-b7b3-ee9945c2239c)

2023-07-13 18:13:03 +00:00

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src/flutter

[Impeller] Switch back to using explicit flush for device buffers. (flutter/engine#43644)

2023-07-13 18:13:03 +00:00