* Add podspec to Flutter iOS framework.

Flutter iOS apps are already pod-enabled, so we might as well turn the
engine framework into a pod, so we don't have to manually copy the
current Flutter.framework into the app directory on every build, but
rather let Cocoapods wire things up for us.

For that to happen, we need a pod spec for Flutter.framework. This spec
will not be published, but rather downloaded as part of the engine
artifacts, and the app's Podfile will have a local path dependency on
it.

* Update licenses_golden...

* Roll Dart to 890dff146ac4733018c059b36bc4d67c45da3232

* uddate licenses

* Flutter content handler initializes ICU data when it starts up

* oops, redundant include

* init ICU before getting the font provider

Allow surface size to be passed by caller
temporarily until we get a proper Display API

* roll dart version to pickup fixes in gen_snapshot

* update licenses

See https://github.com/flutter/flutter/issues/8106

New concepts: FlutterMessageChannel (basic message send/receive superseding existing FlutterView methods), FlutterMethodChannel (method invocation and event streams), pluggable codecs for messages and method calls: unencoded binary, string, json, and 'standard' flutter binary encoding.

Do a glFlush after creating textures on the IO thread before they are used by the GPU thread (#3456)

Fixes https://github.com/flutter/flutter/issues/8431

Bug causing roll-back #3454 has been resolved upstream in tonic.

This reverts commit 0a7b177c.

Reason: broke hot reload when using "package:" style imports for
sources within the same project.

Set the TransparentOccluder shadow flag if the color is not opaque

Fixes https://github.com/flutter/flutter/issues/8429

This contains some fixes for Fuchsia and I'd like to keep the version
of Dart used in fuchsia and flutter builds consistent. Should have no
other impactful changes for Flutter.

Mozart ADD, REMOVE and HOVER phases were going through the default value
of Blink's Cancel type, causing inconsistencies.

Bug: US-157

This change eliminates two previous assumptions:
1. If a Flutter view is embedded in a parent view, that the parent view
   controller would apply any status bar padding necessary.
2. That we should not apply padding unless the flutter view is
   fullscreen.

A simple case where the first assumption fails to hold is a Flutter view
embedded in a UINavigationController with a hidden toolbar. A simple
case where the second assumption fails to hold is a view in a window
whose top overlaps the status bar but isn't fullscreen.

Fixes https://github.com/flutter/flutter/issues/8084

I had added this initially as a means of making it easier to deal with OpenGL directly in Flow. However, we are moving away from dealing with the client rendering APIs directly. Instead, delegating everything to Skia. Besides, we only ever used this to log the GPU description in case of context setup failures. This has not proved to be useful so far. Also, having this in place is making it difficult to remove all dependencies on GL in Shell.

* New mozart input events.

* Adding TODO for keyrepeat

This applies commit 88441bfc0f712ad451784851bfcf0b0cc418ad75 from the
skia_rev_130a118cc68f8f9973e9572356011de378463fea branch to master so
master works in the Fuchsia build again.

Previously we had passed a local generator to flow::BitmapImageCreate /
SkImage::MakeFromGenerator, which takes ownership of the generator.
That generator in turn referenced an SkData backed by a local vector.
The result was an SkImage backed by a deleted buffer.

Merged iOS and Android font fallback mechanisms and push font discovery logic into skia

I'm not sure that this is the right way to do this, but this change causes the Observatory to come up correctly in the content handler.