26050 Add support for zx_channel_write_etc and zx_channel_read_etc. (cla: yes, waiting for tree to go green, platform-fuchsia)

26085 fuchsia: Fix first_layer handling (cla: yes, platform-fuchsia)

26104 [fuchsia] rename SessionConnection to DefaultSessionConnection (cla: yes, waiting for tree to go green, platform-fuchsia)

26114 [fuchsia] migrate shader warmup to be triggered by dart code (cla: yes, platform-fuchsia)

26163 reland output json manifest file in fuchsia_archive (cla: yes, platform-fuchsia)

26166 fuchsia: Improve checking/logging for composition (cla: yes, platform-fuchsia)