* c608b07da bump fuchsia toolchain to clang-12 (flutter/engine#23067)

* 8a3e9a2b9 fix crash in FontCollection::init() when FontFamily is empty (flutter/engine#23019)

* 95ba5ca89 Roll Skia from 6f31e27f1e29 to 85fa75616dfe (7 revisions) (flutter/engine#23118)

* 50e7d8916 [web] Switch web-render option default to auto (flutter/engine#23090)

* 885452086 Roll Skia from 85fa75616dfe to d6f2338ab194 (3 revisions) (flutter/engine#23119)

* acad21c19 [web] Tests for rich paragraph DOM (flutter/engine#23097)

* 27ebbc4bf Rename PointerState.isDown as per style guide (flutter/engine#23120)

* 19950f576 [web] Rich paragraph getBoxesForRange (flutter/engine#23098)

* 581acbe98 Roll Skia from d6f2338ab194 to 1d89532d5988 (1 revision) (flutter/engine#23122)

* 540b1918e Roll Fuchsia Mac SDK from acylwa3i4... to chLTYsKMR... (flutter/engine#23125)

* 3b52edff6 Roll Skia from 1d89532d5988 to 7839f66540b6 (1 revision) (flutter/engine#23126)

* 6b25350af Roll Fuchsia Linux SDK from TIKHoiQyP... to wu6yV-_BL... (flutter/engine#23127)

* 9c72085b7 Roll Skia from 7839f66540b6 to 20f1b3462878 (1 revision) (flutter/engine#23129)

* ee323d0f0 Roll Skia from 20f1b3462878 to 995f0366bd21 (2 revisions) (flutter/engine#23132)

* 625aa695e Roll Skia from 995f0366bd21 to b64da3907f76 (1 revision) (flutter/engine#23135)

* affc4216f Roll Skia from b64da3907f76 to 81da68af2ecf (7 revisions) (flutter/engine#23142)

* 9a6a31e00 Roll Fuchsia Mac SDK from chLTYsKMR... to RDUxjnng0... (flutter/engine#23143)

* 78657edbb Added golden test to make sure that spawn engines work. (flutter/engine#23066)

* bb9cac29a Roll Fuchsia Linux SDK from wu6yV-_BL... to _l04etgVd... (flutter/engine#23145)

* 51c9ae956 Add --strict_null_safety_checks to the Dart flag allowlist (flutter/engine#23144)

* 76310c426 Add missing sdk constriant in pubspec.yaml files. (flutter/engine#23124)

* 6e54f0d2d [fuchsia] Add wrapper for zx_clock_get_monotonic. (flutter/engine#23128)

* ade75e08f [web] Rich paragraph getPositionForOffset (flutter/engine#23133)

* 2ef2c8616 Fix engine in preparation for implementing https://github.com/dart-lang/language/issues/1274 (flutter/engine#23131)

* 9384324cc Update android_lint deps (flutter/engine#23151)

* ea4bb2ae4 Roll Skia from 81da68af2ecf to 7b920446a8fc (14 revisions) (flutter/engine#23152)

* 4b5e4e605 Make it easier to turn on Xcode symlinks (flutter/engine#23150)

* 325f06958 Roll fuchsia toolchain (flutter/engine#23155)

* 05704d312 Use include for C/C++ headers in darwin/macos (flutter/engine#23035)

* 8d3d69b6b Turned no malloc scribble and randomized the tests. (flutter/engine#23014)

* 418cc488e Fix macOS crash when modifier keys pressed. (flutter/engine#23154)

* a8c360dc2 Update FlutterPlatformViewsTests (flutter/engine#23158)

* d941aefa6 [web] Rich text painting on bitmap canvas (flutter/engine#23136)

* 67cb0f382 Revert "[web] Switch web-render option default to auto (#23090)" (flutter/engine#23161)

* c4b48c554 Roll Skia from 7b920446a8fc to dfc880bd9ba0 (14 revisions) (flutter/engine#23164)

* de1de9d44 Disable FlutterPluginAppLifeCycleDelegateTest testWillResignActive (flutter/engine#23166)

Fixes https://github.com/flutter/flutter/issues/71972

* remove flaky flag

* remove from manifest

* fix test

selectionEnabled was not taken into account in:

key movement handling in RenderEditable
mouse drag handling in TextSelectionGestureDetectorBuilder

Add a check that a pubspec file exists before trying to read it.

Fix flutter in preparation for implementing Dart's "Infer non-nullability from local boolean variables" (#72494)

When https://github.com/dart-lang/language/issues/1274 (Infer
non-nullability from local boolean variables) is implemented, flow
analysis will detect that code like this no longer needs to perform a
null check:

    final bool contextIsValid = focus != null && focus.context != null;
    ...
    if (contextIsValid) {
      ... focus! ... // Null check unnecessary
    }

To avoid a build failure due to the unnecessary null check, we need to
temporarily write it in a way that we can ignore it.  Once the feature
is complete and rolled into flutter, I'll remove the null check
entirely.

6edb402ee Roll Skia from f52a8112909c to 632a23afa487 (10 revisions) (flutter/engine#23112) (#72470)

This reverts commit 84a7a611.

InteractiveViewer scale gesture feel improvement.