This reverts commit f2445002.

This reverts commit c59151b1.

This PR rewrites MouseTracker's lifecycle, so that mouse callbacks are all triggered in post frame, instead of the current one where some are triggered during the build phase. This PR also changes the onExit callback to MouseRegion, RenderMouseRegion, and MouseTrackerAnnotation, so that it is no longer triggered on dispose.

* [flutter_driver] [fuchsia] Validate existance of cmx for driver tests

Also added an example driver test that can run on Fuchsia devices.

Fixes: https://github.com/flutter/flutter/issues/45624

* update packages for stock example

* fix licenses

This reverts commit b9a56b9f.

* 8d6fa7e85 Fallback to Roboto if no suitable font is found (flutter/engine#14061)

* 8672e79af Roll src/third_party/skia c96f5108df28..73beaaa48fcc (2 commits) (flutter/engine#14065)

* a86ef9465 Dynamically determine whether to use offscreen surface based on need (flutter/engine#13976)

* 0fc7867ae Roll src/third_party/dart 96e7a4ff30..73fdf19b56 (3 commits) (flutter/engine#14063)

* 6c605f8a9 Fix fml_unittests (flutter/engine#14062)

Revert "Track and use fallback TextAffinity for null affinity platform TextSelections. (#44622)" (#45698)

This reverts commit 6b66d794.

* 29b2e91f1 Include uncommitted files when checking for code format issues. (flutter/engine#14035)

* 7a7118d0a Roll src/third_party/skia 861ac61cb1a9..c96f5108df28 (10 commits) (flutter/engine#14059)

* bc07e6a23 [web] Initial support for LineMetrics (flutter/engine#13985)

* bcb826759 Revert "Do not default to downstream affinity on iOS insertText (#13852)" (flutter/engine#14053)

* 4bdd15cd5 more tests for enabling semantics (flutter/engine#14060)

We keep finding things that we've accidentally not made public. The
pattern we use elsewhere in the platform is to just export everything,
to avoid encouraging people from importing `src/` files directly.

* Relicense Shrine demo to match rest of repository

The Shrine demo was Apache-licensed. The code was mostly
Google-written, with contributions from:

 - Michelle Dudley (@michdud)

 - Abhijeeth Padarthi <rkinabhi@gmail.com> (@rkinabhi)

 - @a14n

I contacted all three, and they confirmed their approval for this
change, as described below.

Abhijeeth Padarthi said by e-mail on Thu, Nov 21, 2019 at 5:48 PM:

> hi Ian,
>
> sure :)
>
> let me know if I need to do anything on my end..

Michelle Dudley wrote by e-mail on Sun, Nov 24, 2019 at 2:07 PM:

> Hi Ian,
>
> That would be ok with me.
>
> Thanks,
>
> Michelle

@a14n said on Discord's Flutter server in the #hackers channel at 10:44PM on Thursday, November 21, 2019:

> @Hixie no problem I agree with this relicensing

* Remove shrine loophole from license checker.

* f61bec846 Pass "null" when copy data is null to iOS pasteboard.string (flutter/engine#14046)

* 268107d2f fixing the method call for testing semantics (flutter/engine#14056)

* 35937eb31 Roll src/third_party/dart 134e0e28cd..96e7a4ff30 (38 commits) (flutter/engine#14058)

* Update project.pbxproj files to say Flutter rather than Chromium

Also, the templates now have an empty organization so that we don't cause people to give their apps a Flutter copyright.

* Update the copyright notice checker to require a standard notice on all files

* Update copyrights on Dart files. (This was a mechanical commit.)

* Fix weird license headers on Dart files that deviate from our conventions; relicense Shrine.

Some were already marked "The Flutter Authors", not clear why. Their
dates have been normalized. Some were missing the blank line after the
license. Some were randomly different in trivial ways for no apparent
reason (e.g. missing the trailing period).

* Clean up the copyrights in non-Dart files. (Manual edits.)

Also, make sure templates don't have copyrights.

* Fix some more ORGANIZATIONNAMEs

This appears to have been inadvertently added in #37497 (333c9618).

The code in question already exists in `_PlatformViewGestureMixin`, which
`PlatformViewRenderBox` (where it was added) mixes in.

Removes an unnecessary leading underscore from a parameter name. The
parameter type is library private, but parameters cannot be 'private'.

Fixes https://github.com/flutter/flutter/issues/45587

fad1b23c4 Roll fuchsia/sdk/core/linux-amd64 from xyyOR... to mSEnz... (flutter/engine#14043) (#45689)


git@github.com:flutter/engine.git/compare/18d74fe45b9c...fad1b23c42b9

git log 18d74fe45b9c..fad1b23c42b9 --first-parent --oneline
2019-11-27 skia-flutter-autoroll@skia.org Roll fuchsia/sdk/core/linux-amd64 from xyyOR... to mSEnz... (#14043)


If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/flutter-engine-flutter-autoroll
Please CC cbracken@google.com on the revert to ensure that a human
is aware of the problem.

To report a problem with the AutoRoller itself, please file a bug:
https://bugs.chromium.org/p/skia/issues/entry?template=Autoroller+Bug

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+/master/autoroll/README.md

* Retry Xcode builds if they fail due to concurrent builds running

Fixes #40576.

* Add tests for concurrent iOS launches

* Increase number of retries to account for the initial build being slow

git@github.com:flutter/engine.git/compare/e3e5f8dabc2e...18d74fe45b9c

git log e3e5f8dabc2e..18d74fe45b9c --first-parent --oneline
2019-11-27 flar@google.com Show test output when engine unit test fails. (#14026)


If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/flutter-engine-flutter-autoroll
Please CC cbracken@google.com on the revert to ensure that a human
is aware of the problem.

To report a problem with the AutoRoller itself, please file a bug:
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git@github.com:flutter/engine.git/compare/2c0eee43923f...e3e5f8dabc2e

git log 2c0eee43923f..e3e5f8dabc2e --first-parent --oneline
2019-11-27 50856934+nturgut@users.noreply.github.com Adding support for enabling semantics on desktop (#14003)


If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/flutter-engine-flutter-autoroll
Please CC cbracken@google.com on the revert to ensure that a human
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To report a problem with the AutoRoller itself, please file a bug:
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git@github.com:flutter/engine.git/compare/5250d6315e7a...2c0eee43923f

git log 5250d6315e7a..2c0eee43923f --first-parent --oneline
2019-11-26 garyq@google.com Always set mEditable values when different in TextPlugin (#13951)
2019-11-26 dnfield@google.com Avoid retaining self in block (#14022)


If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/flutter-engine-flutter-autoroll
Please CC cbracken@google.com on the revert to ensure that a human
is aware of the problem.

To report a problem with the AutoRoller itself, please file a bug:
https://bugs.chromium.org/p/skia/issues/entry?template=Autoroller+Bug

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git@github.com:flutter/engine.git/compare/27fa60793bcb...5250d6315e7a

git log 27fa60793bcb..5250d6315e7a --first-parent --oneline
2019-11-26 skia-flutter-autoroll@skia.org Roll src/third_party/skia 54036c9b8e4b..40a7dfc268b6 (1 commits) (#14016)
2019-11-26 skia-flutter-autoroll@skia.org Roll fuchsia/sdk/core/mac-amd64 from Bxgic... to aVdHP... (#14017)
2019-11-26 skia-flutter-autoroll@skia.org Roll fuchsia/sdk/core/linux-amd64 from kzFUw... to xyyOR... (#14021)
2019-11-26 chinmaygarde@gmail.com Add a separate target for Dart coverter on FML types. (#14011)


If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
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Please CC cbracken@google.com on the revert to ensure that a human
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To report a problem with the AutoRoller itself, please file a bug:
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This PR adds TargetPlatform.macOS to the TargetPlatform enum. This allows us to begin implementation of some adaptive UI based on which target platform is desired.

I haven't updated the tests here, that will come in a follow-up PR.