Slight cleanup of file locations in flutter_tools
to make it easier to see which files are responsible
for data reporting.

Move tools tests into a general.shard directory in preparation to changing how we shard tools tests (#36108)

* Report async callback errors that currently go unreported.
* Add a test

* don't send crash reports if on a user branch.
* add test to test/crash_reporting_test.dart

* Update packages
* Capture JSON RPC errors that presently get swallowed

* some space formattings

* always use blocks in if-else if a block is used

* format spaces in for and while

* allow multiline if conditions

* fix missing space

* add trailing commas on list/map/parameters

* add trailing commas on Invocation with nb of arg>1

* add commas for widget containing widgets

* add trailing commas if instantiation contains trailing comma

* revert bad change

This modifies our flutter_tools crash reports to include the error
message. This error message may contain personally identifying
information (PII), such as a file system path on the developer's
local machine that may contain user names, project code names,
etc. To disable crash reporting, the developer can run the
following command:

    flutter config --no-analytics

For more information on what gets reported during crashes of the
flutter tool, see:

https://github.com/flutter/flutter/wiki/Flutter-CLI-crash-reporting

* enable lint unnecessary_new

* fix tests

* fix tests

* fix tests

* Upgrade everything except matcher.
* Roll matcher (and test)
* Adjust tests that depend on flutter:test directly to depend on a shim
* Require use of package:test shim and remove other references to package:test

Paying off technical debt...

This updates AppContext per the recommendations in #15352

Fixes #15352

* executable.dart#main() depends on runner.dart#run()
* Refactor code such that non-commands don't depend on commands.

No code was actually changed in this PR - code was merely moved from
point A to point B.

* address unused element issues and new warnings

* add a missing return

* enable crash reporting in flutter_tools

* fix analytics text; use relative paths

* fix test

`all.dart` is no longer needed. Furthermore, it causes tests to
be skipped, or to silently fail to run anything.

Fixes #7941

* prefer const constructors

* fix double throw

* add crash reporting without enabling it

* do not drop futures on the floor

* return exitCode from executable run

* debug travis

* remove unnecessary todo

* rename local fs getter