* 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)


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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)


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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)


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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)


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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.

git@github.com:flutter/engine.git/compare/e136d637a873...27fa60793bcb

git log e136d637a873..27fa60793bcb --first-parent --oneline
2019-11-26 30870216+gaaclarke@users.noreply.github.com Added docstring for FlutterOverlayView. (#14019)


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* On flutter tool crash suggest GitHub template

* Shorten GitHub URLs

* Whitespace

* Wording tweak from @InMatrix

* Review edits

* Add additional properties callback in Inspector Serialization Delegate

* Rename _SerializationDelegate to InspectorSerializationDelegate and add test

* Fix indentation

* Remove trailing whitespace

* Handle case when addAdditionalPropertiesCallback returns null

* Improve docs and minor renames

* Improve docs

* Improve documentation

This adds the ability to scroll and page up/down in a Scrollable using the keyboard. Currently, the macOS bindings use Platform.isMacOS as a check, but we'll switch that to be defaultTargetPlatform == TargetPlatform.macOS once that exists.

Resume isolate before terminating tests to prevent flutter_tester leaks in integration tests (#45248)

* Resume isolate before terminating tests to prevent flutter_tester leak

* Fix lint

* Catch exceptions from resume() as well as timeout()

* Formatting fixes

* Don't try to resume if there's no vm service

* Fix handling of timeouts to not leak futures

git@github.com:flutter/engine.git/compare/96cba6c92a8a...e136d637a873

git log 96cba6c92a8a..e136d637a873 --first-parent --oneline
2019-11-26 skia-flutter-autoroll@skia.org Roll fuchsia/sdk/core/mac-amd64 from 1nxSz... to Bxgic... (#14014)
2019-11-26 skia-flutter-autoroll@skia.org Roll src/third_party/skia 4f90f9d83183..54036c9b8e4b (4 commits) (#14013)


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git@github.com:flutter/engine.git/compare/05f8c8b24b92...96cba6c92a8a

git log 05f8c8b24b92..96cba6c92a8a --first-parent --oneline
2019-11-26 skia-flutter-autoroll@skia.org Roll src/third_party/skia 8fa469d3bcd6..4f90f9d83183 (4 commits) (#14012)
2019-11-26 hterkelsen@users.noreply.github.com Refactor CanvasKit backend in preparation for platform views (#13935)
2019-11-26 iska.kaushik@gmail.com [vulkan] Bundle vulkan validation layer so files (#13930)
2019-11-25 chinmaygarde@google.com Don't crash but warn when the scene builder specifies no layers. (#14008)
2019-11-25 franciscojma@google.com Remove device independent mask (#14010)


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git@github.com:flutter/engine.git/compare/298e053bdc04...05f8c8b24b92

git log 298e053bdc04..05f8c8b24b92 --first-parent --oneline
2019-11-25 skia-flutter-autoroll@skia.org Roll src/third_party/skia 50299de39976..8fa469d3bcd6 (21 commits) (#14009)
2019-11-25 jason-simmons@users.noreply.github.com Convert images to raster on the GPU thread for Image.toByteData (#13647)
2019-11-25 dworsham@google.com Fix most fml tests on Fuchsia (#14007)
2019-11-25 bkonyi@google.com Roll src/third_party/dart d5fa596d74..134e0e28cd (9 commits) (#14006)
2019-11-25 amirh@users.noreply.github.com revert accidental change to MultipePlatformViewsTest (#13481)


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* implicit-casts:false in flutter/lib/src/gestures

* address review comments

This fixes an unreported bug in the macOS key handling where for some remote access situations, the modifier mask is set to the "any modifier" mask without any side specified (e.g. modifierShift bit is specified and not modifierLeftShift bit).

git@github.com:flutter/engine.git/compare/c89ac6347b7e...298e053bdc04

git log c89ac6347b7e..298e053bdc04 --first-parent --oneline
2019-11-25 jonahwilliams@google.com Add support for FontLoader API for the web (#13999)
2019-11-25 brianosman@google.com Use new SkPathDirection enum, previous one is deprecated (#14005)
2019-11-25 skia-flutter-autoroll@skia.org Roll src/third_party/skia c3ff97a98b74..50299de39976 (1 commits) (#13998)


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c89ac6347 Roll fuchsia/sdk/core/linux-amd64 from _7JyV... to hK-BD... (flutter/engine#13997) (#45565)


git@github.com:flutter/engine.git/compare/b0d2caceab25...c89ac6347b7e

git log b0d2caceab25..c89ac6347b7e --first-parent --oneline
2019-11-25 skia-flutter-autoroll@skia.org Roll fuchsia/sdk/core/linux-amd64 from _7JyV... to hK-BD... (#13997)


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git@github.com:flutter/engine.git/compare/b6b54fd60631...b0d2caceab25

git log b6b54fd60631..b0d2caceab25 --first-parent --oneline
2019-11-25 skia-flutter-autoroll@skia.org Roll fuchsia/sdk/core/mac-amd64 from Q9HKI... to 1nxSz... (#13995)
2019-11-25 30870216+gaaclarke@users.noreply.github.com Removed auto roll commits from auto_assign. (#13992)


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There has been some confusion about whether or not
.flutter-plugins-dependencies should be tracked in version control or
not. Added a comment to both it and .flutter-plugins explaining that
it's generated and shouldn't be.

.flutter-plugins-dependencies is parsed through JSON, and the JSON spec
doesn't support comments. So unfortunately the note is living in an
arbitrary "_info" key instead of an obvious top level comment.

Analyzer warning.