Add MediaPlayer methods for volume and looping

Check the image decoder's failed flag after obtaining the frame buffer

Some decoders (e.g. JPEG) do not execute the decode until the call to
frameBufferAtIndex.  If the decode fails, we should not try to return a
bitmap.

Add patched-yasm back to DEPS for use by libjpeg_turbo

rev engine

Revert to libjpeg_turbo

We had switched to libjpeg, but libjpeg was failing to decode images when
built with the defines in our .gn files

rev engine

In SoundPool, have the client provide stream IDs

In SoundPool, have the client provide stream IDs so future API calls aren't gated on completion of Play()

Also use an array to represent channel volumes instead of assuming two channels

rev engine

Build script used by builders to package the unified Xcode project

Switch snapshotter and application runner based on Xcode target

Remove //third_party/BUILD.gn

We no longer need this hack to mux between libjpeg and libjpeg_turbo.

Roll Skia

Remove references to files in the generated directory as those are no longer added directly in an Xcode build phase

Fix iOS builds after updates to media.mojom

Remove re2

We don't use this anymore.

Remove //url

We don't use this anymore.

Remove libxml and modp_b64

These were used only for base's test framework, which we don't need.

Remove OpenTypeSantizer and brotli

We don't need OpenTypeSantizer or brotli because we don't support loading fonts
over the network. Instead, fonts will need to be packaged inside the Flutter
asset bundle.

Remove unused code

We don't use yasm, libjpeg_turbo, or mojo's devtools.

Update to mojo b7c8cb12f05d3bc1351e65a4f9a84c5d1bcd1704

Automatically switch to using script snapshots on iOS simulator