Currently, we listen to keyboard events to find out which keys should be represented in RawKeyboard.instance.keysPressed, but that's not sufficient to represent the physical state of the keys, since modifier keys could have been pressed when the overall app did not have keyboard focus (especially on desktop platforms).

This PR synchronizes the list of modifier keys in keysPressed with the modifier key flags that are present in the raw key event so that they can be relied upon to represent the current state of the keyboard. When synchronizing these states, we don't send any new key events, since they didn't happen when the app had keyboard focus, but if you ask "is this key down", we'll give the right answer

git@github.com:flutter/engine.git/compare/6c763bb551cb...8ebb31840134

git log 6c763bb551cb..8ebb31840134 --no-merges --oneline
2019-11-06 47866232+chunhtai@users.noreply.github.com Revert "Issues/39832 reland (#13642)" (flutter/engine#13720)
2019-11-06 chinmaygarde@google.com Ensure that the device pixel ratio is taken into account with window metrics in physical pixels. (flutter/engine#13708)
2019-11-06 jason-simmons@users.noreply.github.com Fix NPE in splash screen lookup (flutter/engine#13719)
2019-11-06 skia-flutter-autoroll@skia.org Roll src/third_party/skia 6e54a299cce9..6790423f84ef (11 commits) (flutter/engine#13718)
2019-11-06 bkonyi@google.com Roll src/third_party/dart 24f1f313a2..462a448ac8 (2 commits)
2019-11-06 bkonyi@google.com Roll src/third_party/dart 80fc4d54e5..24f1f313a2 (5 commits)
2019-11-06 skia-flutter-autoroll@skia.org Roll src/third_party/skia f00524707da7..6e54a299cce9 (1 commits) (flutter/engine#13715)
2019-11-06 skia-flutter-autoroll@skia.org Roll fuchsia/sdk/core/mac-amd64 from bCFtP... to 6Du8E... (flutter/engine#13714)
2019-11-06 bkonyi@google.com Roll src/third_party/dart 51016532e8..80fc4d54e5 (2 commits)
2019-11-06 skia-flutter-autoroll@skia.org Roll src/third_party/skia cdc0c23f1a2e..f00524707da7 (2 commits) (flutter/engine#13712)
2019-11-06 bkonyi@google.com Roll src/third_party/dart 8bdca37e98..51016532e8 (21 commits)
2019-11-06 skia-flutter-autoroll@skia.org Roll src/third_party/skia f3d4109a793b..cdc0c23f1a2e (36 commits) (flutter/engine#13707)
2019-11-06 matthew-carroll@users.noreply.github.com Fix splash screen lookup. (#44131) (flutter/engine#13660)
2019-11-06 gspencergoog@users.noreply.github.com Fix editing selection and deletion on macOS (flutter/engine#13702)
2019-11-06 mouad.debbar@gmail.com [web] Don't send keyboard events from text fields to flutter (flutter/engine#13699)


If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
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To report a problem with the AutoRoller itself, please file a bug:
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* Use l10n tool to generate stocks i18n files

* Rename *_en_EN.arb to *_en_US.arb

* Fix l10n script

There are cases where we have access to the observatory without having a device connection accessible.

This reverts commit 289b4588.

git@github.com:flutter/engine.git/compare/6c763bb551cb...9726b4cb99d3

git log 6c763bb551cb..9726b4cb99d3 --no-merges --oneline
2019-11-06 skia-flutter-autoroll@skia.org Roll src/third_party/skia f3d4109a793b..cdc0c23f1a2e (36 commits) (flutter/engine#13707)
2019-11-06 matthew-carroll@users.noreply.github.com Fix splash screen lookup. (#44131) (flutter/engine#13660)
2019-11-06 gspencergoog@users.noreply.github.com Fix editing selection and deletion on macOS (flutter/engine#13702)
2019-11-06 mouad.debbar@gmail.com [web] Don't send keyboard events from text fields to flutter (flutter/engine#13699)


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 garyq@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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Documentation for the AutoRoller is here:
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Allow ProjectFileInvalidator to be overridden with a different
implementation.

I stole this from https://github.com/flutter/flutter/pull/39217.

git@github.com:flutter/engine.git/compare/05ab04dbe8cf...6c763bb551cb

git log 05ab04dbe8cf..6c763bb551cb --no-merges --oneline
2019-11-06 fmil@google.com [fuchsia] Temporarily disable intl provider (flutter/engine#13696)
2019-11-05 matthew-carroll@users.noreply.github.com Fix plugin registrant reflection path. (#44161) (flutter/engine#13698)
2019-11-05 darrenaustin@google.com Added Semantic header support on Android. (flutter/engine#13262)


If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
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* added new lfecycle state

* update

* update

This missed some plugins that _do_ support the v1 embedding
(shared_preferences as one known case) so caused unexpected breakages.

This reverts commit b94c1a41.

git@github.com:flutter/engine.git/compare/7b968ff95ff1...0928c1af2f45

git log 7b968ff95ff1..0928c1af2f45 --no-merges --oneline
2019-11-05 garyq@google.com Add 'Cough' test font and support multiple test fonts. (flutter/engine#13649)
2019-11-05 skia-flutter-autoroll@skia.org Roll src/third_party/skia 4cc2dc64ff13..4a4f34b76f3a (19 commits) (flutter/engine#13637)


If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
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Please CC garyq@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 makes the flutter tool download the debug symbols for Flutter and Dart runners to be used in Fuchsia dev environment.

This reverts commit a214b462.

* Add Material Study app Rally to examples

Adds the CupertinoContextMenu widget for iOS 13 support.

Fixes #42049.

git@github.com:flutter/engine.git/compare/e73c9c8f6bd5...7b968ff95ff1

git log e73c9c8f6bd5..7b968ff95ff1 --no-merges --oneline
2019-11-05 chinmaygarde@google.com Ensure that the CAMetalLayer FBO attachments can be read from. (flutter/engine#13643)
2019-11-04 47866232+chunhtai@users.noreply.github.com Revert "Added new lifecycle enum (#11913)" (flutter/engine#13632)
2019-11-04 47866232+chunhtai@users.noreply.github.com Added new lifecycle enum (flutter/engine#11913)


If this roll has caused a breakage, revert this CL and stop the roller
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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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git@github.com:flutter/engine.git/compare/0a8bd9dd6fbb...e73c9c8f6bd5

git log 0a8bd9dd6fbb..e73c9c8f6bd5 --no-merges --oneline
2019-11-04 skia-flutter-autoroll@skia.org Roll src/third_party/skia 8e083eee8ece..4cc2dc64ff13 (1 commits) (flutter/engine#13543)
2019-11-04 skia-flutter-autoroll@skia.org Roll fuchsia/sdk/core/mac-amd64 from ggsQ5... to XcaoM... (flutter/engine#13535)
2019-11-04 yjbanov@google.com fix getBoxesForRange for zero-length ranges (flutter/engine#13483)
2019-11-04 bkonyi@google.com Roll src/third_party/dart bbe2ac28c9..ab5cf0f854 (73 commits) (flutter/engine#13614)
2019-11-02 skia-flutter-autoroll@skia.org Roll src/third_party/skia 283ec65f632a..8e083eee8ece (32 commits) (flutter/engine#13489)
2019-11-02 skia-flutter-autoroll@skia.org Roll fuchsia/sdk/core/mac-amd64 from FKqQ_... to ggsQ5... (flutter/engine#13490)
2019-11-02 xster@google.com Release shim bindings when detaching (flutter/engine#13432)
2019-11-01 gw280@google.com Add fuchsia.intl.PropertyProvider to our services on Fuchsia (flutter/engine#13486)
2019-11-01 fmil@google.com [dart] Makes the intl services available (flutter/engine#13460)
2019-11-01 skia-flutter-autoroll@skia.org Roll fuchsia/sdk/core/linux-amd64 from 866GG... to dhwMR... (flutter/engine#13475)
2019-11-01 skia-flutter-autoroll@skia.org Roll fuchsia/sdk/core/mac-amd64 from JngMB... to FKqQ_... (flutter/engine#13477)
2019-11-01 skia-flutter-autoroll@skia.org Roll src/third_party/skia 809ec77893be..283ec65f632a (14 commits) (flutter/engine#13472)
2019-11-01 dnfield@google.com Request a reattach when creating the text input plugin on Android (flutter/engine#13474)


If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
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*Starting with arb files in lib/l10n, the tool creates the following by default:
1. An AppLocalizations class containing:
- an `AppLocalizationsDelegate`
- a `supportedLocales` property that returns a list of all supported locales.
- a `localizationsDelegate` property that returns a list containing this delegate along with `GlobalMaterialLocalizations.delegate`, `GlobalCupertinoLocalizations.delegate`, and `GlobalWidgetsLocalizations.delegate`.
2. One Dart `message_<locale>.dart` file for each arb file, as well as a `messages_all.dart` file that performs the locale message lookup. The tool infers the locale of each arb file from the @@Locale property or the arb file's name.

* Adjust and refactor all FlatButton tests into its respective file