(cloned from https://github.com/flutter/flutter/pull/26399)

https://github.com/flutter/engine/compare/e5ec3cf3ea5c...b7f6bf0192d1

git log e5ec3cf3ea5ce78c6c3116271601f60d30a799d4..b7f6bf0192d175ac2c245f27524c5195140ecd50 --no-merges --oneline
b7f6bf019 Pass deadline to embedder idle notification callback (flutter/engine#7444)
5272805f1 Fix settings.advisory_script_uri in iOS createShell (flutter/engine#7235)
788dea5dd Eliminate std::string using directive (flutter/engine#7433)
cd98f6bdb Clear the font collection's cache when a font is dynamically loaded (flutter/engine#7436)
dea6a0849 Remove legacy and deprecated defaultClipBehavior (flutter/engine#7439)
5749b75af Temporary revert of Dart SDK rolls made since 2019/01/08 (flutter/engine#7437)
29c70f5fc Roll src/third_party/skia 292ece8024ea..d2fa7e33798c (8 commits) (flutter/engine#7434)
37d886ef8 Simplify rollback of dynamic patches (flutter/engine#7432)
6071286ef Download dynamic patch to separate file, then rename it to install. (flutter/engine#7428)
4c9136bdb Roll src/third_party/dart cb966bdce7a0a9d0c34149b50ae5704676cf34c8..651d19cdaa25d020b8f7c193c907644284029130 (4 commits) 651d19cdaa Ignore --fast-startup flag, assume true aeb7fccd5b Fix plugin start up to work with OverlayResourceProvider 0b0704c7c4 [vm] Use std::abs instead of regular abs(). 36b5fe0c7a Track how many analysis server requests had latency info
239f16e72 Roll src/third_party/dart 927b0cb9edda5500fed0acbd60c04487d3e526e6..cb966bdce7a0a9d0c34149b50ae5704676cf34c8 (1 commits) cb966bdce7 Unify parsing of co19 test options and regular test options.
2501eb42e Roll src/third_party/dart f4986cc78ddd884e60e7274c44f31dbcd990b912..927b0cb9edda5500fed0acbd60c04487d3e526e6 (73 commits)927b0cb9ed [vm/aot] Support optimization of modulo against a power-of-two. bf13ac85c4 Ensure LSP server clears diagnostics for removed files/analysis roots 54fffe4cca Add support for LSP workspace/didChangeWorkspaceFolders e7b783ba5d Fix bug with deprecated rootPath + add tests ad300b904d Improve handling of server-specific analysis diagnostics pages 1d096d8499 Enable the analyzer Diagnostics server for LSP 6bb1dcdfa4 Fix wording e749576caa [VM/Compiler/AOT] Do not populate unused arguments descriptor in bare instructions mode a1250467fe Move member conflict detection to own method
39a99b005 Docs improvements per @Hixie's comments (flutter/engine#7387)
26e02aaa2 Wire up support for external OpenGL textures for the embedder. (flutter/engine#7087)
20d70d2bf Eliminate unused import of ZipException (flutter/engine#7429)
b972f75db Allow embedders to add per shell idle notification callbacks. (flutter/engine#7427)
844d27cb3 Refactor dynamic patching to use clearer naming and structure. (flutter/engine#7426)
99fa3901a Roll src/third_party/skia 3560ea702f1b..292ece8024ea (9 commits) (flutter/engine#7424)
97ff4b226 Dart SDK roll for 2019-01-09
39b2e4b02 Roll src/third_party/skia 76dc683364c2..3560ea702f1b (10 commits) (flutter/engine#7420)
88e212f99 Dart SDK roll for 2019-01-09
82d3208d4 Roll src/third_party/skia 1337f5b85978..76dc683364c2 (18 commits) (flutter/engine#7418)
8657340c8 Dart SDK roll for 2019-01-09
a369ef606 Dart SDK roll for 2019-01-08
3ae5eb8c1 Dart SDK roll for 2019-01-08
42f449fa4 remove deprecated updateNode argument (flutter/engine#7413)
5e33f33a1 Refactor shared code into separate function to simplify further work. (flutter/engine#7410)
937ee8bf9 Cleanup dead code (flutter/engine#7409)

The AutoRoll server is located here: https://autoroll.skia.org/r/flutter-engine-flutter-autoroll

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

If the roll is causing failures, please contact the current sheriff (cbracken@google.com), and stop
the roller if necessary.

This adds some functions to the interface for RawKeyEventData and all subclasses that allow the recipient of an event to determine which modifier keys are currently being pressed without needing to know the specific modifier bitmasks for the platform.

Also adds constants for the modifier bitmasks for each platform, for completeness (and because I needed them anyhow to implement the above).

Added tests for the RawKeyEventData subclasses, and modified the raw_keyboard manual test app to show modifier keys being pressed. I also separated the different platform-specific subclasses into separate files.

Fixes #26155.

* Revert "move analysis_options to package (#26244)"

This reverts commit d4d1b29a.

* move analysis_options to package

Usages of ParagraphConstraints (from dart:ui) whose constructor could be
const as of flutter/engine#7346 are currently marked //
ignore:prefer_const_constructors in the framework until all
Google-internal embedders have been updated to an engine version that
includes the above change. These were initially updated in engine roll
flutter/flutter#26252, but broke internal embedders.

We should re-enable use of the const constructor in those cases once
internal embedders are updated.

See: https://github.com/flutter/flutter/issues/26390

80 characters was short enough that after the XML boilerplate in the
response, all we got was 'The'.

When downloading the ObjC/Java API docs, check the HTTP response status
code and if not 200, attempt up to 5 times before giving up.

Disables the cache by default and deprecates the API for setting its
size.

flutter/flutter#26081

Now that we have our DNS mapping we should refer to the master docs site that way everywhere.

* Added the superellipse (a.k.a. squircle) shape to flutter, which is needed to recreate some cupertino components, e.g. buttons in pixel-perfect detail (issue #13914).

* Add some basic tests for evaluating expressions in `flutter test`

* Review tweaks

* [WIP] BAB theme

* [WIP] BAB theme

* Update goldens

* Extract helper function in tests

* Update Goldens version

* Add tests

* [WIP] Hans first round comments

* Added test

* Added docs

* Hans second round comments

* Fixed analyzer error

* Hans third round comments

* ambient

* Change [BottomAppBarTheme.of] to static

* Final doc change

* Add a validator to ensure NO_PROXY is set correctly if HTTP_PROXY is set

Fixes #24854.

* Fix typo

* Dummy edit to try and force update of PR desc on Cirrus

* Revert "Check for duplicative Flutter.framework emeddings when building for Xcode 10 (#23188)"

Before this change, rolling back a patch relied on deleting the patch
file from the server completely. This PR implements a more reliable
approach where developer needs to create a physical rollback patch file.
This is more robust to mistakenly taking down a patch from user devices.

When setting the Fuchsia logging function, it should happen before any
initialization code, as init can still cause warning/error/info messages
to get printed to logs. Since the default stderr/stdout fd's aren't
correct, this can cause a program to crash for unclear reasons.

* update docs for editable_text (TextField)

* typo, clarify behavior when lines > 1

* Check for bad configuration in Xcode10

Fix project directory has spaces lead to compile error when use 'flutter create -t module'command (#23817)

The variable isn't interpolating because it's using "${}" when ruby uses "#{}".

* the onStart callback will report the location of the pointer where it wins the gesture arena by default instead of the pointer down location. Fixes all tests related to changing this default value.

* Remove *.lock from gitignore

* Remove pubspec.lock from gitignore

* Add source line to snippet metadata

* Parse sourceLine as an int