This is intended to match the exit codes returned by the Dart command line tool

* Roll Dart SDK to ed00447138f95ea4ba612509a244ca8205735372

Make the VM happy with a spurious instruction snapshot.

* Revert "Snapshots: Don't use an empty array where a NULL array is expected. (#3361)"

This reverts commit 275ffdce.

Broke iOS simulator builds; should no longer be necessary after rolling
the Dart SDK to ed00447138f95ea4ba612509a244ca8205735372.

On iOS simulator builds, we were seeing DartLookupSymbolInLibrary return
a pointer to a address of the snapshot data rather than the address of
the snapshot buffer itself. On simulator builds we don't build the
snapshot data into a buffer in app.dylib (kDartVmSnapshotData) but link
it statically into the engine itself.

Adapt to refactoring of snapshot APIs in the Dart VM.

* Roll Dart SDK to b43da048c31a16b9993de1536406ed014ef73ffd

* Update licenses.golden for Dart SDK

* Update LICENSE for sky_engine

* Roll Dart SDK to 3a422bceb76d6155cab0c728b68f2badad8ff0e9

* Update licences.golden for latest Dart SDK

try 2.

* Update Skia revision to pull in GL native interface construction fixes on iOS.

Fixed in https://skia-review.googlesource.com/c/5212/

* Use the new image encoder API from Skia.

This requires an updated buildroot.

* The lastchange hook wrote a file no one ever read.
* We don’t need binutils because we don’t use debug fission on Linux.
* We dont use eu-strip.

Update DartServiceIsolate/FlutterView because VMServiceIO_NotifyServerState
now provides a URI for the observatory

Instead, just use JNI and Objective-C directly.