This change adds support for armv7, arm64, and universal iOS apps.

This change eliminates iOS target architecture hardcoding (previously
arm64 only) and uses the target architecture(s) specified in Xcode's
ARCHS setting ('Architectures' in Xcode Build Settings).

For universal binaries, set ARCHS to its default value, $(ARCHS_STANDARD).

Note that after changing the architecture in Xcode, developers should
run 'pod install' from the ios subdirectory of their project. A separate
change (that will land before this one) will add support for
automatically detecting project file and Podfile changes and re-running
pod install if necessary.

This change also adds an --ios-arch option to flutter build aot. In iOS
AOT builds (in profile and release mode), this dictates which
architectures are built into App.framework. This flag should generally
be unnecessary to set manually since flutter build aot is typically only
invoked internally by flutter itself.

The new values are not ready for use yet inside Google

If the developer changes their Xcode build settings and their project
has plugins, pod install is required, (e.g. to pick up changes to the
target architecture).

Similarly, manual edits to the Podfile should trigger a pod install.

* Roll engine to e976be13c51448f89107d082ec81e2b6731671fa

* move away from deprecated constants

iOS debug builds always run in interpreted mode whether on device or on
simulator. In both cases, we can skip snapshotting and link against an
empty App.framework. Previously, we did this for iOS simulator builds.
This does the same for device builds.

Previously, debug iOS builds used gen_snapshot to generate a core
snapshot, then used 'xxd' to generate C files containing the snapshot
data in buffers named kDartVmSnapshotData and kDartIsolateSnapshotData,
which are then compiled/linked into App.framework. This is unnecessary
since the VM compiled into Flutter.framework already contains this data.

This fixes and re-lands 4bb7496b, which
was reverted in ceade39c due to test
failures caused by a bad rebase.

This reverts commit 4bb7496b.

Allows for better mockability when tests are added.

Makes for easier mocking, particularly for testing AOT snapshot build.

Fixes #13655

Revert 9749bea7. Accidentally pushed to flutter instead of fork repo for PR.

This reverts commit 9749bea7.

add --buildNumber and --buildName to flutter build like
flutter build apk --buildNumber=42 --buildName=1.0.42

* Let iOS auto-signing tool handle Googler scenario

* Forgot to update tests

This updates AppContext per the recommendations in #15352

Fixes #15352

* fail ios workflow when simctl does not work

* missed rename commit

* address comments

* Revert "Revert "Add android license verification to doctor and some refactoring" (#14727)"

This reverts commit d2602947.

* Add tests, fix sdkManagerEnv and use it consistently, and rearrange Status object model

* AnsiSpinner needs to leave the cursor where it found it.

* fix tests

* Const constructor warning only shows up on windows...?

* Avoid crash if we can't find the home directory

* Make pathVarSeparator return a string in the mock

* Implement review comments

* Fix out-of-order problem on stop

* Created plumbing but has stream problem

* testing with makePipe

* Trying pipe but not really getting anywhere

* works by repeatedly reading line

* Minor cleanup

* works

* Clean up pipe after use.

* Move the last status forward

* Make sure failed script commands bubble up

This reverts commit b3e4976c.

Work around xcodebuild's undocumented freeze when -showBuildSettings is used with -allowProvisioning* (#14684)

* Revert "Revert "Reduce xcodebuild noise #2" (#14641)"

This reverts commit 2d47481f.

* Stop scrapping xcodebuild output, get the right build settings

* clone the command params first

Let Xcode communicate with Apple and create new provisioning profiles and register new devices (#14589)

Merging to get back to a green tree.

* Revert "Revert "Reduce noise in xcodebuild stdout (#14586)" (#14605)"

This reverts commit 8e2278bd.

* Specify the build config when cleaning

This reverts commit 74ddda51.

* Reduce noise in xcodebuild stdout

* Reduce output from cleaning, from non failing xcode outputs and from script

* Check xcodebuild clean's exit code

* Revert "Reduce noise in xcodebuild stdout"

This reverts commit 222a26f55f2a3fc7b115e8a65e55c9be36f241bd.

Previously, the iOS ApplicationPackage subclasses did not mark the
bundleID constructor parameter as @required. This is passed up to the
ApplicationPackage constructor as the id parameter which is already
marked @required and is asserted to be non-null.