Fixes #18995.

This logic is described in the test as looking for a scroll ending
very close to a new page, but in fact its behavior is more like
"very close to a page to the right": if we're not very, very close
to any page, it will pick the page to the left, not an old page.

There's no reason this should be left-right asymmetrical.
Instead, pick the nearest page.

In practice, the case where this makes a difference never arises when
the scroll runs undisturbed to completion; but when the user taps on
the page to hold or drag, the scroll will be interrupted before it
gets within tolerance of a particular page, and this case does arise.

This fixes a glitch that is hard to trigger without time dilation,
but is quite conspicuous with it:

 * Open a tab view with at least 4 tabs, e.g. the Buttons screen
   of the gallery (with "Animate Slowly" on.)
 * Starting at tab 0, tap tab 2.
 * When the animation is nearly complete, tap the page a couple
   of times, as if to drag it around to scroll.  Then let the
   page view settle ballistically toward page 2.
 * Before it finishes, tap tab 3.
 * Suddenly page 1 fills the view, replacing page 2, before we
   scroll from there to page 3.

With this fix, the animation in the last step moves smoothly from
where we are when it starts onward to page 3.

Also:
 * Export TextInputAction from `text_field.dart` to parallel `TextInputType`.

Before a severe log would be raised when timeout happens. Now that
testing connections requires potentially running into a timeout, this
will cause failures when there shouldn't be any.

See https://github.com/flutter/flutter/pull/18881#discussion_r199285256

* Support all keyboard actions. (#11344)

Fixes #18829

Otherwise on Windows these will fail as an unsupported platform when things try to read defaultTargetPlatform in flutter apps.

This fixes #18727 

Goldens for flutter/flutter#18729

Our first step towards https://github.com/flutter/flutter/issues/18727

This test was designed to ensure flutter_tester keeps running (previously it would quit immediately). However it's turned out ot be rather flaky and we have new tests on the way that supersede this by actually testing real things (debug stepping, reloading, expression evaluation).

* Remove the 'app' domain from flutter daemon

By default the daemon won't register the "app" domain, you need to opt-in (which the 'run' command does, as well as the tests for the app functionality).

Fixes #6658.

* Tweak text

* Put restart/callServiceExtension/stop back into daemon mode

* Add a comment about removing discoverApps

* Fix typo

* Add emulator.create to Daemon API

* Swap order of daemon changelog entries

Add iOS module template

This will enable integration of flutter-views into existing iOS project.

See https://github.com/flutter/flutter/issues/13379#issuecomment-400984667.

This reverts commit 8be198d8 that broke the build.

After landing the un-skip this test failed with a timeout. It then passed on the next build (!). I think it's too flaky to leave running until we can better diagnose what's happening.

Add iOS module template

This will enable integration of flutter-views into existing iOS project.

* Add process output for flutter_tester test and unskip

* Add a comment about this potential flake

* Add --create option to flutter emulators

* Tweaks to error message

* Simplify emulator search logic

* Make name optional

* Add a note about this option being used with --create

* Tweaks to help information

* Switch to processManager for easier testing

* Don't crash on missing files or missing properties in Android Emulator

* Move name suffixing into emulator manager

This allows it to be tested in the EmulatorManager tests and also used by daemon later if desired.

* Pass the context's android SDK through so it can be mocked by tests

* Misc fixes

* Add tests around emulator creation

Process calls are mocked to avoid needing a real SDK (and to be fast). Full integration tests may be useful, but may require ensuring all build environments etc. are set up correctly.

* Simplify avdManagerPath

Previous changes were to emulatorPath!

* Fix lint errors

* Fix incorrect file exgtension for Windows

* Fix an issue where no system images would crash

reduce throws on an empty collection.

* Fix "null" appearing in error messages

The name we attempted to use will now always be returned, even in the case of failure.

* Add additional info to missing-system-image failure message

On Windows after installing Andriod Studio I didn't have any of these and got this message. Installing with sdkmanager fixed the issue.

* Fix thrown errors

runResult had a toString() but we moved to ProcessResult when switching to ProcessManager to this ended up throwing "Instance of ProcessResult".

* Fix package import

* Fix more package imports

* Move mock implementation into Mock class

There seemed to be issues using Lists in args with Mockito that I couldn't figure out (docs say to use typed() but I couldn't make this compile with these lists still)..

* Rename method that's ambigious now we have create

* Handle where there's no avd path

* Add another toList() :(

* Remove comment that was rewritten

* Fix forbidden import

* Make optional arg more obviously optional

* Reformat doc

* Note that we create a pixel device in help text

* Make this a named arg

Fixes https://github.com/flutter/flutter/issues/18007

This is an attempt to reland #18488 with less breakage on macOS.

This also improves diagnostic in case of internal compiler errors.

See #18879.

This reverts commit 5d8ea59d.

* Improve update checking

This change emables pinging the server to check for updates regardless of whether the local version is "out of date". The server code already has a 7-day cache so the result is that we can now ping the server once every 7 days instead of waiting for the local install to be 4 weeks out of date before pinging.

The original 4 week period is still used for when we'll start warning the user they're out of date if we could not confirm with the server whether there's a new version.

* Improve message when we know there's a new version available

* Fix bnullable bool checks

* Switch nullable bool to enum

* Fix casing of enum values

* Remove stale comment

The names are now descriptive so doesn't need additional explanation.

* Improve name of function

* Remove note:

* Rename kPauseToLetUserReadTheMessage -> timeToPauseToLetUserReadTheMessage

* Change kVersionAgeConsideredUpToDate to 5 weeks from 4

* Inline the isNewerFrameworkVersionAvailable check

* Fix indenting (?)

* Fix more indenting

* Rename function to be clearer it's getting the commit date

* Formating tweaks

* Update stamp when connection failed, and reduce time before we'll try again

Previously we would hit the server on every command if we thought we might be out of date and we never successfully connected (eg. if you're offline). This makes the stamp update even when there's a conneciton failure so that this won't happen, but reduces the time till we check again from 7 days to 3 days to compensate a little in case it was a one-off.

https://github.com/flutter/flutter/pull/18193#issuecomment-399222269

* Fix comment

* Don't perform update checks if not on an official channel

This test is failing on mac_bot (but passing elsewhere) because flutter-tester is apparently quitting earlier than expected. Locally it fails with an even weirder error and almost all tests are failing with "Compilation failed" (this isn't happening on the builds, so something is bad on my MacBook). Marking as skip to fix build while investigating; there's no real impact of this test not running; it's testing a tool that its itself used for testing (and not currently in any way that should be affected by this failure).