Fixes https://github.com/flutter/flutter/issues/22370

* Report hot reload statistic

* Lints

* Introduce custom dimensions identifiers to track hot reload stats

716185fb7 Roll src/third_party/skia 125f76790131..b282e1f622f6 (1 commits) (flutter/engine#7380) (#26118)


https://github.com/flutter/engine/compare/cd0de779eadd...716185fb7955

git log cd0de779eadd367531df00b6ff693b02009595e8..716185fb7955fe6480964336e674a5c68048a6c1 --no-merges --oneline
716185fb7 Roll src/third_party/skia 125f76790131..b282e1f622f6 (1 commits) (flutter/engine#7380)

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https://github.com/flutter/engine/compare/83239e141b09...cd0de779eadd

git log 83239e141b090aabe0e95fe8be8057c5710be89e..cd0de779eadd367531df00b6ff693b02009595e8 --no-merges --oneline
cd0de779e Roll src/third_party/skia 5e710e13a55b..125f76790131 (1 commits) (flutter/engine#7379)
7ded1d3d6 Roll src/third_party/skia 3d5b488e5cd7..5e710e13a55b (1 commits) (flutter/engine#7378)
bcc7dcbe7 Revert "Test SDK roll" (flutter/engine#7374)
ee83c383b Roll src/third_party/skia 275eaff3be4b..3d5b488e5cd7 (9 commits) (flutter/engine#7372)
a4450af55 Dart SDK roll for 2019-01-04
b35f021a8 Update GetCallbackHandle to use Dart_IsTearOff instead of a string comparison (flutter/engine#7324)
4ea457355 Roll src/third_party/skia 18df87ec8bda..275eaff3be4b (7 commits) (flutter/engine#7369)
27eaab4f6 Roll src/third_party/skia 5f1692c60a43..18df87ec8bda (12 commits) (flutter/engine#7368)
9fb8f8bdf Roll src/third_party/skia c519fed6ddce..5f1692c60a43 (1 commits) (flutter/engine#7367)

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

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https://github.com/flutter/engine/compare/e52287a1b557...83239e141b09

git log e52287a1b5572c73b19d085ccbe404f0aeddb5f6..83239e141b090aabe0e95fe8be8057c5710be89e --no-merges --oneline
83239e141 Roll src/third_party/skia 76616a10a786..c519fed6ddce (3 commits) (flutter/engine#7366)
62b9594d2 Roll src/third_party/skia 4683942a45f6..76616a10a786 (8 commits) (flutter/engine#7365)
23d087420 Roll Dart to version ec86471ccc47a62df8b4009e1fb37c66ff9dc91b (flutter/engine#7363)
78f6eb5c8 Roll src/third_party/skia 3b7e65107f67..4683942a45f6 (10 commits) (flutter/engine#7362)

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Cirrus puts the PR description and commit message in environment
variables.
These messages tend to have non ASCII characters sometimes (like
emojis), which triggers a Gradle bug (gradle/gradle#3117) resulting
in Gradle crashing without a helpful error message.

The real solution to this problem should be fixing the Gradle bug.
The better workaround on the Flutter side would be to set a UTF8 locale
on the Cirrus machine, but I have yet figured out how to do it.
For now to avoid more people from hitting this I'm working around by
temporarily unsetting the Cirrus environment variables with the PR
description and commit message.

A non ASCII character to make sure it works: 😄

https://github.com/flutter/engine/compare/134b65ec6034...e52287a1b557

git log 134b65ec6034cdd9823ed5631df248d27870306e..e52287a1b5572c73b19d085ccbe404f0aeddb5f6 --no-merges --oneline
e52287a1b Fix typo clas -> class (flutter/engine#7360)
80c19b6b1 Roll src/third_party/skia 8966b55644c2..3b7e65107f67 (3 commits) (flutter/engine#7361)
beed0c455 Roll src/third_party/skia fdde2926df92..8966b55644c2 (1 commits) (flutter/engine#7359)

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* Ensure all errors thrown by image providers can be caught by developers.

Add an `onError` parameter to the ImageCache.putIfAbsent method.
In the event that an error is thrown when resolving an image, catch if
this parameter is provided. Use the onError parameter to ensure that all
errors thrown are forwarded to the ImageStream error channel instead of
directly into the void.

https://github.com/flutter/engine/compare/2940812ab26a...134b65ec6034

git log 2940812ab26a9dac772459888f1e79389bedb977..134b65ec6034cdd9823ed5631df248d27870306e --no-merges --oneline
134b65ec6 Roll src/third_party/skia aae6ae39a356..fdde2926df92 (1 commits) (flutter/engine#7358)
f97edf2ac Roll src/third_party/skia 96345a23dfa9..aae6ae39a356 (1 commits) (flutter/engine#7357)
d051c47e5 Roll src/third_party/skia bc84adceaada..96345a23dfa9 (2 commits) (flutter/engine#7356)
15fcba4d8 Roll src/third_party/skia d0d5bb8c8500..bc84adceaada (6 commits) (flutter/engine#7355)
4d353de49 Preparing to remove SK_SUPPORT_LEGACY_PAINT_TEXTMEASURE (flutter/engine#7354)
54d7c4256 Paint all backgrounds first to prevent overlap (flutter/engine#7287)
0ad16dd10 Roll src/third_party/skia 279b65ddb5a3..d0d5bb8c8500 (12 commits) (flutter/engine#7353)
8cca33aea Give more control over when dynamic patches get downloaded and installed. (flutter/engine#7327)
2d291c7ff Roll src/third_party/skia 8f37ce5b9f2c..279b65ddb5a3 (6 commits) (flutter/engine#7350)

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

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the roller if necessary.

* Add didSendFirstFrameEvent service extension.

2940812ab Roll src/third_party/skia 1409ac718693..8f37ce5b9f2c (2 commits) (flutter/engine#7349) (#25978)

https://github.com/flutter/engine/compare/b1a9a6e79474...844c3274e6a1

git log b1a9a6e7947492b27c21688104d2d006d583094e..844c3274e6a1cd5a4651c46d26761b76ea837b34 --no-merges --oneline
844c3274e Roll src/third_party/skia 22451ccae544..1409ac718693 (2 commits) (flutter/engine#7348)
8ae205ccf Roll src/third_party/skia db0fdfbf107d..22451ccae544 (1 commits) (flutter/engine#7347)
e04cb414c Roll src/third_party/skia 247f03baeed9..db0fdfbf107d (1 commits) (flutter/engine#7345)
5f5316871 Roll src/third_party/skia 4f050fb81955..247f03baeed9 (1 commits) (flutter/engine#7344)
0e4a1afc3 Roll src/third_party/skia 8f42e2467cd9..4f050fb81955 (1 commits) (flutter/engine#7343)
a19b78ab6 Roll src/third_party/skia 9bc33b963844..8f42e2467cd9 (1 commits) (flutter/engine#7342)

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

Documentation for the AutoRoller is here:
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If the roll is causing failures, please contact the current sheriff (liyuqian@google.com), and stop
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https://github.com/flutter/engine/compare/995e3247fe50...b1a9a6e79474

git log 995e3247fe500ff6e9981bd6e2409191c4f9a32a..b1a9a6e7947492b27c21688104d2d006d583094e --no-merges --oneline
b1a9a6e79 Roll src/third_party/skia 61b3d1d00057..9bc33b963844 (1 commits) (flutter/engine#7341)
571bf5c1e Roll src/third_party/skia 7b0f0149474a..61b3d1d00057 (1 commits) (flutter/engine#7340)
193cf3792 Roll src/third_party/skia 197b1f7900a2..7b0f0149474a (1 commits) (flutter/engine#7334)
8b35c97c1 Roll src/third_party/skia 0c1592291580..197b1f7900a2 (2 commits) (flutter/engine#7333)
544e5bcd2 Roll src/third_party/skia 3b0a332fd970..0c1592291580 (1 commits) (flutter/engine#7332)
d2eb6efeb Roll src/third_party/skia a5d2a9486fed..3b0a332fd970 (1 commits) (flutter/engine#7331)
e2ca868c3 Roll src/third_party/skia 3dc21675b05a..a5d2a9486fed (1 commits) (flutter/engine#7330)
cdc7cc8d3 Roll src/third_party/skia 739b760deaa6..3dc21675b05a (1 commits) (flutter/engine#7329)
e548f12e4 Roll src/third_party/skia aec8c7e280cb..739b760deaa6 (1 commits) (flutter/engine#7328)

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

Documentation for the AutoRoller is here:
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If the roll is causing failures, please contact the current sheriff (liyuqian@google.com), and stop
the roller if necessary.

https://github.com/flutter/engine/compare/1bd9d41f8990...995e3247fe50

git log 1bd9d41f8990..995e3247fe50 --no-merges --oneline
995e3247f Roll src/third_party/skia f3e6b90461e4..aec8c7e280cb (1 commits) (flutter/engine#7326)
6f763fbad Minor refactoring of dynamic patching code. (flutter/engine#7325)
868dc047b Support loading flutter assets from dynamic patch (flutter/engine#7308)

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See https://github.com/flutter/flutter/issues/25855

https://github.com/flutter/engine/compare/f0a1d6f91d93...1bd9d41f8990

git log f0a1d6f91d93..1bd9d41f8990 --no-merges --oneline
1bd9d41f8 Roll src/third_party/skia 51eaa79d19b8..f3e6b90461e4 (5 commits) (flutter/engine#7323)
bf863786c Roll buildroot to pick up changes since the last roll: (flutter/engine#7322)
c716a21a2 Roll src/third_party/skia 7561dba7c145..51eaa79d19b8 (3 commits) (flutter/engine#7321)
189662feb Roll src/third_party/skia 3e7ba8fa7e7f..7561dba7c145 (1 commits) (flutter/engine#7320)
db5214d3d Roll src/third_party/skia acc763e8795c..3e7ba8fa7e7f (1 commits) (flutter/engine#7319)
0a0d61323 Changes since last dart roll: (flutter/engine#7316)

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

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```
f0a1d6f91 Roll src/third_party/skia 487132b82826..acc763e8795c (1 commits) (#7318)
f0dd6436c Recreate the overlay rendering surfaces if the GrContext was changed. (#7317)
245317a62  Reland "Only reject gestures to embedded UIViews when the framework sa (#7315)
be69b07cc Roll src/third_party/skia d2fa2eb59f2d..487132b82826 (1 commits) (#7314)
732ea7669 Allow dynamic patches without a patch number. (#7309)
20ee4e3e9 Revert "Only reject gestures to embedded UIViews when the framework says so. (#7307)" (#7313)
28e152f7e Roll src/third_party/skia cae020ae5f5f..d2fa2eb59f2d (3 commits) (#7312)
7c65290da Roll src/third_party/skia 31c1bf89657f..cae020ae5f5f (1 commits) (#7311)
180d8a7d9 Roll src/third_party/skia f6e963ef91c2..31c1bf89657f (1 commits) (#7310)
cc9c6702d Only reject gestures to embedded UIViews when the framework says so. (#7307)
2fb2b2729 Roll src/third_party/skia 3605fde88b2a..f6e963ef91c2 (1 commits) (#7306)
```

Unique patch numbers are mainly useful for canary and A-B testing, but otherwise complicate things and can now be omitted.

* Collect devfs stats for better analytics

* Fix fields initialization

* Fix lints