* Roll dart dep

* Roll dartdoc dep

* Update license hash, ignore changes to file list

* Use BinaryPrinter instead of KernelSerializer to accomodate IKG

* Close sink opened with openWrite

Use a generic sans-serif font family on Android that will be recognized by Skia's font manager (#4055)

 - Assumes only the Dart VM is interested in idle notification.
 - Gives the VM the time remaining in each frame.
 - Gives the VM 100ms if there is no pending frame.

Issue flutter/flutter#9594

See https://github.com/flutter/engine/pull/4043

This repository contains FTL now in the Fuchsia build.

We're moving the FIDL library to a new path. This patch updates the GN
dependency.

Revert "Re-enable Unicode ZWJ handling code that had been disabled pending an ICU update (#4035)" (#4036)

This reverts commit afd2e6b8.

Fuchsia is still using an older version of ICU that does not support this.

Also temporarily disable a unit test that failed without the reverted patch.

* Roll lib/tonic dependency forward

* Update signature hash, ignore changes to the file list

* Roll dart forward

* Roll dart to latest b7ef001fec0eacd6451ae71746d0a0ef090aac59

* Update license hash, ignore changes to the file list

GN check can't understand preprocessor defines, so we have to disable
checking for these conditionally included headers.

After the DEPS updates, we use Unicode 9.0 and so these workarounds are not necessary. I re-ran all the EmojiTests to verify.

See https://github.com/flutter/engine/pull/3964

* order

* comment fix

* review comments

This will allow us to use the common font fixtures.