* Update dart deps and add create_sdk for host builds

* Set and use is_flutter flag

* Update to make it compatible with latest changes in https://codereview.chromium.org/2998503002/

* Fix deps

* Roll dart dependency to pick up new arguments

* Merge

* Update deps

* Update license

* roll Dart to 21eddc429e9c7260de00a9af7cad94baba830f59

* update licenses

Roll Dart to 69817eea182384b40ef658d578fd49cac00c5874

This updates our compilers, GN and Ninja binaries.

The new `dart_observatory_pub_packages_rev` dependent on the rolled `dart_revision` required the update of the licensing files

* Roll Skia and enable API guards
* Update licenses

flutter/flutter#11238

This reverts commit dafdcee5.

This commit broke the Windows engine build, though the logs are missing so it is unclear why.

https://github.com/flutter/flutter/issues/11238

Roll Dart to be95b916ddf0af2b204286a438e7169e3bb2c67a.

* Roll Dart to 1bfd01c1f7a57fed039ce8ab95df2a5f14cf63b6

* fix licence

Roll Dart VM to daa38a2ea21d290e45adb509dc60418b22ec7eba for fix to Thumb profile sample collection.

Roll buildroot to b0b836db790abff26695a944224a4934480f2f48.

Roll Dart to f445c318184b30b3db997ac27f357bcb5d45670a.

Fuchsia issue TO-365

* Roll dart and buildroot deps since they have to be updated together to get and use prebuilt dart sdk in correct location.

* Update license

* Build Flutter patched-sdk with kernel artifacts

* Switch to new dart_host_toolchain argument mechanism to let dart patch_sdk know of host_toolchain.

* Update dart dependency

* Updated licenses

* Rename dart dependencies tag so they have just 'dart_'-prefixed dart's names.

* Fix indentation and line breaks for newly added deps.

* Add toolchain for windows host

* Update dart revision

* Licenses

* Update licenses

* Revert changes to licenses_third_party

* Roll Skia

* Update licenses

* Revert "Fix licenses_lib golden file (#3798)"

This reverts commit d8ac43c3.

* Revert "Remove ParagraphConstriants (#3796)"

This reverts commit 8ccf767f.

* Revert "Reland "Initial integration of libtxt with Flutter alongside Blink." (#3793)"

This reverts commit 3c049219.

* Transition to Hybrid lib/txt and blink text system.

This reverts commit 1e9e134d.