These now match what 2016.3 expects.

Q: What happens if we set time dilation to zero?
A: It would be bad.

@hixie told me to add me to the list, see https://github.com/flutter/flutter/pull/6833#issuecomment-260418501

Fixes #5695

* Fixes Analysis Server regression (https://github.com/dart-lang/sdk/issues/27856).
* Adds `front_end` dependency override (required by analyzer).

- [x] Remove the two stage initial boot process.
- [x] Remove the loader screen app.
- [x] Don't report reload times for the initial reload because we are
switching from a snapshot to source and that will always be worst case.

Declares a top-level getter that returns the outputs directory to which
Flutter Driver tests can write any output files. Timeline data defaults
to this directory.

#6972 

Fixes #6963

This patch replaces uses of Flexible with Expanded where we're using
FlexFit.tight. We still need to think of a better name for the
FlexFit.loose variant.

Also, improve the docs for Row, Column, Flex, and RenderFlex to be more
problem-oriented and to give a complete account of the layout algorithn.

Fixes #6960
Fixes #5169

* Add delay between writing file and modifying it

* Add type argument

- [x] Make iOS and Android application startup paths consisitent.
- [x] Remove the now unncessary Android specific special cases from the runners.

This allows us to run the analyzer CLI on packages and correctly find dart:ui.

- [x] Stop unnecessarily building the flx a second time on startup.
- [x] Stop unncessarily copying the flx to the device a second time on startup.
- [x] Remove `startBundle` and move logic into `startApp`.