This change re-introduces skipping snapshot builds if input sources (and
outputs) have not changed since the last snapshot build, with a bugfix
to include the entry-point source in the checksum used to check whether
rebuild can be skipped. This ensures that the following sequence
invalidates the cached build, resulting in two snapshot builds:

  flutter build ios lib/foo.dart
  flutter build ios lib/bar.dart

This reverts commit 3d5afb5a.

* Allow tapping on TabBar indicator to switch tabs

* fix semantics

* review comments

Roll engine in order to fix regression of AOT snapshot build time.

I forgot to do this when I updated our test package.

The most recent Flutter IntelliJ plugin replaces FLUTTER_MODULE with
WEB_MODULE and eliminates the exclusion of packages/ directories.
Use of the packages/ directory was turned off by default months ago, and
is replaced by the .packages file.

* Adds more customization options to the Chip widget

Includes:
- Custom Tooltip message for the delete button;
- Custom background color for the chip
- Custom delete icon color
- Custom label text style

* Adds missing type annotations to tests and improves documentation.

* Tweaks labelStyle field documentation

Also, add tests to verify that our coverage is actually being tested!

* Adding tests for animationStatus

* remove comments

* animateTo is allways forward

* clearify docs

* review comments

It was previously possible for event dispatch to occurr during the
brief window where the tree had been marked dirty but before it had
been relaid out by reassemble, which would cause assertions to fire if
someone did a hot reload while touching the device.

* Do not schedule animation if already at the target value

* Partially fixes https://github.com/flutter/flutter/issues/11495.
* Also includes a fix for Cupertino button to always run the tap animation even if the finger is immediately lifted from the screen (uncovered by a test failure).

* refactorings

* more tests

* test clearifications

* remove Listener

* fix lints

* fix async issue

In a Travis environment, the test package is exiting the process after
completing the tests.
See dart-lang/test@d1057c4

The flutter test command calls the test package's main() and then expects to
do other work afterward.  The exit prevents flutter test from writing the
new coverage results, causing the coveralls tool to run against an old
lcov.info file.

This reverts commit 0cfd3dec239faf3c13ce759df15ddab226545e8c.

Do not throw if a hot reload is attempted when all Flutter instances on the device have been stopped (#11504)

This can happen if an Android host app has been paused but its process is still running

Add Diagnosticable base class and documentation

* FadeInImage: shows a placeholder while loading then fades in

* fix dartdoc quotes

* license headers; imports

* use ImageProvider; docs; constructors

* _resolveImage when placeholder changes

* address comments

* docs re ImageProvider changes; unsubscribe from placeholder

* rebase

* address comments

* refactor commands_test to choose a free port for the service protocol

* discover the service protocol port

* add a todo

* Revert "Support space- and backslash-escaped dependencies (#11090)"

This reverts commit e6bafd0b.

* Revert "Skip AOT snapshot build if inputs are unchanged (#11084)"

This reverts commit b5e522e2.

* perform the initial poll for devices quicker

* add a Poller class

* test the new Poller class

This reverts commit 5d9db106.

* PopupMenuButton: create IconButton if child is Icon

Otherwise the resulting button has an abnormally small and rectangular
area. With multiple PopupMenuButton(child: Icon) they get squished
together in the AppBar.

* Add separate icon argument to PopupMenuButton

* Fix style issues and tweak dartdocs

* Add tests for icon argument to PopupMenuButton

* Group icon tests and fix broken test, analyzer warnings

* Test that the correct custom icon is present

* Apply De Morgan's to work around dart analyzer bug

see: https://github.com/dart-lang/sdk/issues/30288

* Revert "Make plugins add their repos to projects in the consuming app (#11447)"

This reverts commit abe1e252.

* Revert "Support for custom build types on Android (#11354)"

This reverts commit 87eec719.

* Revert "add a profile() method (#11443)"

This reverts commit 561d17a8.

* Revert "Fix documentation based on dartdoc's warnings (#11428)"

This reverts commit 6655074b.

* Revert "Improve some docs around WillPopScope. (#11429)"

This reverts commit 58a28a29.

* Revert "temporarily disable broken driver test in integration_ui (#11440)"

This reverts commit 764515ec.

* Revert "style fix"

This reverts commit 00bfc866.

* Revert "tests for waitFor/waitForAbsent"

This reverts commit 31d2ee9c.

* Revert "Always evaluate the finder in `driver.waitFor()` and `driver.waitForAbsent()`"

This reverts commit 11d7c79b.

* roll

* no-op commit

* revert no-op

It has recently come to light that we may have been ordering saveLayer
calls and clip calls incorrectly.