-* Inserted an `IconTheme` widget under `CupertinoTheme` to provide a default icon color when using `CupertinoTheme`.
* Changed `CupertinoTheme` to a `StatelessWidget`, to match the implementation of `Theme`
* Changed the nesting order of `Theme`'s sub widgets, to let `Theme.iconTheme` take precedence, so that `Theme`'s behavior is kept as is.

https://github.com/flutter/engine/compare/2fe4439178f3...6bc33b5e1442

git log 2fe4439178f3e09ddaa4d016688691a1adc65ed6..6bc33b5e144254ceab274298dd61d9d9ed0dcc8f --no-merges --oneline
6bc33b5e1 Android Embedding PR24: Allow FlutterActivity to provide an engine, also adjust FlutterFragment timing to avoid Activity launch lag. (flutter/engine#8448)
08a133508 More detailed comments for engine build windows VM (flutter/engine#8456)
1854b8571 Roll src/third_party/dart a2709992a2..907c514c89 (1 commits)

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2fe443917 Roll src/third_party/skia 558637996569..0e35ce27e0e9 (11 commits) (flutter/engine#8454) (#30567)


https://github.com/flutter/engine/compare/7e79b1f03db0...2fe4439178f3

git log 7e79b1f03db04a70509a207d5a0ce2de498f9aba..2fe4439178f3e09ddaa4d016688691a1adc65ed6 --no-merges --oneline
2fe443917 Roll src/third_party/skia 558637996569..0e35ce27e0e9 (11 commits) (flutter/engine#8454)

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* Correctly synthesise buttons, and add tests

https://github.com/flutter/engine/compare/3c3b26b55c16...7e79b1f03db0

git log 3c3b26b55c1682cbf58a712d102c66dca53f93e4..7e79b1f03db04a70509a207d5a0ce2de498f9aba --no-merges --oneline
7e79b1f03 Roll src/third_party/dart 896f1c4bb9..a2709992a2 (25 commits)
9c4c043ae Roll src/third_party/skia 604d5a3fca01..558637996569 (1 commits) (flutter/engine#8452)
754453df3 Roll src/third_party/skia 1f58a8e457ba..604d5a3fca01 (1 commits) (flutter/engine#8451)
d6d45da07 Roll src/third_party/skia b0ababfe5ad2..1f58a8e457ba (3 commits) (flutter/engine#8450)

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Fixes a crash that happened when attempting to select text in trackpad mode on iOS.

3c3b26b55 Roll src/third_party/skia 51874e3e3712..b0ababfe5ad2 (1 commits) (flutter/engine#8449) (#30540)


https://github.com/flutter/engine/compare/697e541a8d94...3c3b26b55c16

git log 697e541a8d9475b504a2bd6f335b4f004775adf3..3c3b26b55c1682cbf58a712d102c66dca53f93e4 --no-merges --oneline
3c3b26b55 Roll src/third_party/skia 51874e3e3712..b0ababfe5ad2 (1 commits) (flutter/engine#8449)

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The current repair command for Arch Linux is no longer valid because
`lib32-libstdc++5` had been removed from multilib.

Actually, `lib32-gcc-libs` from core just work.
Also see https://github.com/flutter/flutter/issues/25035

https://github.com/flutter/engine/compare/8b74cba20bb8...697e541a8d94

git log 8b74cba20bb878d1e75747200f75dfaff5925bda..697e541a8d9475b504a2bd6f335b4f004775adf3 --no-merges --oneline
697e541a8 Add scripts that prepares our windows VM image (flutter/engine#8446)

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https://github.com/flutter/engine/compare/219bf5938752...8b74cba20bb8

git log 219bf5938752e0030b491565af1910c137b83dd8..8b74cba20bb878d1e75747200f75dfaff5925bda --no-merges --oneline
8b74cba20 Make sure FlutterViewController flushs all pending touches when no longer active (flutter/engine#8400)
06cab8171 Roll src/third_party/skia e4628b10722f..51874e3e3712 (2 commits) (flutter/engine#8445)
5460926c0 Roll src/third_party/dart 9814cb1b9c..896f1c4bb9 (4 commits)
694fc5677 Build windows engine on GCE (flutter/engine#8442)

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* Add constants `kPrimaryButton`, `kTouchContact` and `kStylusContact`
* PointerDownEvent and PointerMoveEvent will always set the 0x01 bit on buttons

Fix MaterialApp's _navigatorObserver so it doesn't cause WidgetApp's assertion to fail when using custom navigator, fixes #18904

https://github.com/flutter/engine/compare/0f70d5d4f1e3...219bf5938752

git log 0f70d5d4f1e3ed377781bc6e73e3666c73afc7f8..219bf5938752e0030b491565af1910c137b83dd8 --no-merges --oneline
219bf5938 Roll src/third_party/skia 1383a38e1d92..e4628b10722f (12 commits) (flutter/engine#8443)
a40adfdf4 Add window title/icon support to GLFW shell (flutter/engine#8435)

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https://github.com/flutter/engine/compare/5944867cabdb...0f70d5d4f1e3

git log 5944867cabdb934ef9fea0dccb865cb1acef51b5..0f70d5d4f1e3ed377781bc6e73e3666c73afc7f8 --no-merges --oneline
0f70d5d4f Roll src/third_party/dart 600b2831ef..9814cb1b9c (7 commits)
4b1ec56bc Roll src/third_party/skia f346df396a23..1383a38e1d92 (8 commits) (flutter/engine#8440)

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Adds the "2D Transformations" demo to the gallery, which shows how to do things such as navigate around a map a la Google Maps, or show a full screen zoomable photo.  The idea is to abstract this code into a first class widget soon.

* Fix: ui.PointerChange.remove might contain position change, but we used to expand it into a Cancel and Remove, neither of which allows position change. A Hover event is added, and a test is updated accordingly.
* Fixed the issue where a PointerMoveEvent and a PointerCancelEvent do not receive the correct pressure.
* Refactor the calculation of delta into deltaTo.

https://github.com/flutter/engine/compare/ad9d2417e9aa...5944867cabdb

git log ad9d2417e9aa182700f0d1423de758d2a000598d..5944867cabdb934ef9fea0dccb865cb1acef51b5 --no-merges --oneline
5944867ca update to use SkTileMode (flutter/engine#8439)

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https://github.com/flutter/engine/compare/309d078b597d...ad9d2417e9aa

git log 309d078b597d3a38fe9bcef8d8bae7b56487e8eb..ad9d2417e9aa182700f0d1423de758d2a000598d --no-merges --oneline
ad9d2417e Roll src/third_party/skia dde12a25bb5e..f346df396a23 (1 commits) (flutter/engine#8438)
0ed237c19 Roll src/third_party/skia b6d04556c34d..dde12a25bb5e (4 commits) (flutter/engine#8437)
445ab42ef Roll src/third_party/dart 11a3dd7332..600b2831ef (9 commits)
49d0dc6d6 Roll src/third_party/skia 5c5de2146309..b6d04556c34d (1 commits) (flutter/engine#8434)
4ff18fbda Roll src/third_party/dart f6768b6fb3..11a3dd7332 (56 commits)
7b831986f Roll src/third_party/skia 2273c900ea28..5c5de2146309 (5 commits) (flutter/engine#8432)
800ea0a40 Revert "Enable shutting down all root isolates in a VM. (#8402)" (flutter/engine#8431)
b59c4436c Enable shutting down all root isolates in a VM. (flutter/engine#8402)
9acdf1837 Make AccessibilityViewEmbedder final (flutter/engine#8429)
804d54ddf Eliminate unused displayBounds parameter (flutter/engine#8427)
d4c815f57 Roll buildroot (flutter/engine#8425)
20190d707 Roll src/third_party/skia fbe240669394..2273c900ea28 (13 commits) (flutter/engine#8428)
7e38b0aa2 Revert "Revert "Separate the data required to bootstrap the VM into its own class. (#8397)" (#8406)" (flutter/engine#8414)
d8bb9d793 Roll src/third_party/skia 176da0bb8a10..fbe240669394 (9 commits) (flutter/engine#8424)
64fc58329 Remove use of DART_CHECK_VALID. (flutter/engine#8417)

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309d078b5 Roll src/third_party/skia e25b4472cdd9..176da0bb8a10 (10 commits) (flutter/engine#8422) (#30441)


https://github.com/flutter/engine/compare/cc115500b9cb...309d078b597d

git log cc115500b9cb2b27d59627f202e6cd6bb87f49fc..309d078b597d3a38fe9bcef8d8bae7b56487e8eb --no-merges --oneline
309d078b5 Roll src/third_party/skia e25b4472cdd9..176da0bb8a10 (10 commits) (flutter/engine#8422)

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This reverts commit ffbb335e.

Reason for revert: flutter driver tests may have bugs in getting
first frame. Revert this until we figure out what happened.