The empty benchmark-report TextEdit held .height(rest(1)) beside
content.height(rest(2)), so it reserved a third of the window at every
launch and pushed the composer two thirds down -- Iris's 11:39 phone
report. It is sized to its content now, capped and scrollable, and sits
above the transcript rather than under the composer.
New log::info! lines for one insets change, one surface_changed, one
renderer build and one surface_destroyed, each with the glyph/atlas
counts, so a phone's adb logcat can answer the app-switch text loss the
emulator cannot reproduce.