Record E7's second constraint, and that the premise held (#226)

Doing #226 turned up a second obstacle underneath E7's, with the same
cause. The obvious way to avoid driving the app was a host Activity in
androidTest owning its own CreateDocument launcher; it cannot be started at
all, because instrumentation runs in the target app's process and the
component is in the instrumentation one. That is the same fact as E7's
second bullet arriving from the other side, and it leaves the app's own
Save button as the only launcher available to drive.

And the answer #226 was filed for: on API 34, stock DocumentsUI hands back
a document URI reporting a size of exactly zero, so destinationIsKnownEmpty
can return true and D4's fix is live rather than inert.

A "no defect found", and not one that could have been reached by reading --
which is the argument for having done it.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

docs/e2e-read-findings.md

@@ -1,6 +1,6 @@
 # E2E-read findings
 
-**Status:** seven findings; E4 fixed, the rest standing, none urgent — **plus one confirmed vacuous test, which is a
+**Status:** seven findings; E4 fixed, E7 extended and its ticket closed, the rest standing — **plus one confirmed vacuous test, which is a
 ticket rather than an entry here** (see [Not covered here](#not-covered-here)). `E1`–`E6` came from
 the 2026-09-05 read of the instrumented suite. Every entry here is a *test-suite* observation —
 something a new test would not fix, because the test already exists and the problem is what it
@@ -274,6 +274,27 @@ ticket is about.
 **So any test of `publish` against a real `DocumentsProvider` must drive DocumentsUI**, and pays
 #190's flake tax. The work is one item at that cost, not two, and #226 was updated to say so.
 
+**Updated 2026-09-06, doing it: there is a second constraint underneath, and it has the same
+cause.** The obvious way to avoid driving the app was a host Activity in `androidTest` owning its
+own `CreateDocument` launcher. It cannot be started at all:
+
+```
+java.lang.RuntimeException: Intent in process org.libremediaconverter resolved to different
+  process org.libremediaconverter.test
+    at android.app.Instrumentation.startActivitySync
+```
+
+Instrumentation runs in the target app's process, so a component declared in the instrumentation
+APK is in the wrong one — the same fact that sinks approach 2 above, arriving from the other side.
+**The app's own Save button is the only launcher available to drive**, which is also the more
+faithful thing to drive. `SafPickerRoundTripTest.aSaveWritesToTheDocumentTheSystemPickerCreated` is
+what came of it.
+
+**And the premise turned out to be true**, which is the answer #226 was filed for: on API 34,
+stock DocumentsUI hands back a document URI reporting a size of exactly zero. `deletePartialOutput`
+can fire, and D4's fix is live rather than inert. A "no defect found" — and not one that could have
+been reached by reading.
+
 ### What this does *not* block, which is the useful half
 
 `FFmpegKitConfig.getSafParameterForRead` — the bridge on every real conversion and join — needs no
@@ -361,7 +382,7 @@ decision, not a detail — see **E6** for why no third option exists — and **#
 | **#223** | `HardwareFallbackTest` never attempts the hardware path on any emulator leg | closed — it skips instead of passing vacuously |
 | **#224** | Cancelling a *running* native session, in any of the three engines | closed — all three engines |
 | **#225** | No `content://` input has reached a *successful* conversion — the ffkitsaf bridge | closed, and it found **#238** |
-| **#226** | `OutputPublisher.publish` against a real `DocumentsProvider` | **open** — re-scoped by E7; one picker-driven item, not two |
+| **#226** | `OutputPublisher.publish` against a real `DocumentsProvider` | closed — the premise holds; see E7 |
 | **#227** | The notification's Cancel action has never been fired | closed |
 | **#228** | `encodesFlacLosslessAudio` and `encodesOpus` pass on any non-empty file | closed |
 | **#229** | FFmpeg's progress percentage is computed everywhere and asserted nowhere | closed |