Issue 1:
Steps to Reproduce

Run flutter doctor after downloading flutter.

Logs

None, it's failing on doctor.

Flutter Doctor

Updating flutter tool...

FINE: Pub 2.0.0-edge.0d5cf900b021bf5c9fa593ffa12b15bcd1cc5fe0

IO : Spawning "cmd /c ver" in C:\flutter\packages\flutter_tools.

IO : Finished ver. Exit code 0.

| stdout:

| |

| | Microsoft Windows [versÃ£o 10.0.16299.248]

| Nothing output on stderr.

MSG : Resolving dependencies...

SLVR: Solving dependencies:

| - coverage 0.10.0 from hosted (coverage)

| - test 0.12.30+3 from hosted (test)

| - file 2.3.6 from hosted (file)

| - mustache 1.0.0 from hosted (mustache)

| - meta 1.1.2 from hosted (meta)

| - web_socket_channel 1.0.7 from hosted (web_socket_channel)

| - http 0.11.3+16 from hosted (http)

| - xml 2.6.0 from hosted (xml)

| - json_rpc_2 2.0.7 from hosted (json_rpc_2)

| - stream_channel 1.6.3 from hosted (stream_channel)

| - process 2.0.7 from hosted (process)

| - vm_service_client 0.2.4+1 from hosted (vm_service_client)

| - front_end any from hosted (front_end)

| - linter 0.1.43 from hosted (linter)

| - quiver 0.28.0 from hosted (quiver)

| - args 1.3.0 from hosted (args)

| - package_config 1.0.3 from hosted (package_config)

| - crypto 2.0.2+1 from hosted (crypto)

| - platform 2.1.2 from hosted (platform)

| - plugin 0.2.0+2 from hosted (plugin)

| - stack_trace 1.9.1 from hosted (stack_trace)

| - usage 3.3.0 from hosted (usage)

| - intl 0.15.2 from hosted (intl)

| - archive 1.0.33 from hosted (archive)

| - cli_util 0.1.2+1 from hosted (cli_util)

| - json_schema 1.0.8 from hosted (json_schema)

| - yaml 2.1.13 from hosted (yaml)

| - analyzer any from hosted (analyzer)

IO : Get versions from https://pub.dartlang.org/api/packages/coverage.

IO : HTTP GET https://pub.dartlang.org/api/packages/coverage

| Accept: application/vnd.pub.v2+json

| X-Pub-OS: windows

| X-Pub-Command: upgrade

| X-Pub-Session-ID: 4536270E-0F24-47AF-975D-67B3DAA7A98C

| X-Pub-Environment: :flutter_install

| X-Pub-Reason: direct

| user-agent: Dart pub 2.0.0-edge.0d5cf900b021bf5c9fa593ffa12b15bcd1cc5fe0

Error: Unable to 'pub upgrade' flutter tool. Retrying in five seconds...

This gets looped continuously.

Issue 2:
ubuntu 17.04

环境搭建遇到错误

git clone -b alpha https://github.com/flutter/flutter.git

evanyan@ps:~$ flutter doctor
Building flutter tool...
The setter 'readEventsEnabled=' was called on null.
Receiver: null
Tried calling: readEventsEnabled=false
package:pub/src/source/hosted.dart 338 BoundHostedSource._throwFriendlyError
package:pub/src/source/hosted.dart 140 BoundHostedSource.doGetVersions
===== asynchronous gap ===========================
package:pub/src/source.dart 165 BoundSource.getVersions
package:pub/src/solver/version_solver.dart 231 SolverCache.getVersions.<fn>
dart:async runZoned
package:pub/src/http.dart 228 withDependencyType
package:pub/src/solver/version_solver.dart 230 SolverCache.getVersions
===== asynchronous gap ===========================
package:pub/src/solver/unselected_package_queue.dart 121 UnselectedPackageQueue._getNumVersions
===== asynchronous gap ===========================
package:pub/src/solver/unselected_package_queue.dart 50 UnselectedPackageQueue.add
===== asynchronous gap ===========================
package:pub/src/solver/version_selection.dart 68 VersionSelection.select.<fn>
===== asynchronous gap ===========================
dart:async _completeOnAsyncReturn
package:pub/src/solver/version_selection.dart 70 VersionSelection.select.<fn>
dart:async _completeOnAsyncReturn
package:pub/src/solver/unselected_package_queue.dart 54 UnselectedPackageQueue.add
dart:async _completeOnAsyncReturn
package:pub/src/solver/unselected_package_queue.dart 128 UnselectedPackageQueue._getNumVersions
dart:async _Completer.completeError
package:pub/src/solver/version_solver.dart 254 SolverCache.getVersions
dart:async _Completer.completeError
package:pub/src/source/hosted.dart 153 BoundHostedSource.doGetVersions
dart:async _Completer.completeError
package:http/src/base_client.dart 172 BaseClient._sendUnstreamed
dart:async _Completer.completeError
package:http_throttle/http_throttle.dart 51 ThrottleClient.send
dart:async _Completer.completeError
package:pub/src/http.dart 127 _PubHttpClient.send
dart:async _Completer.completeError
package:http/src/io_client.dart 66 IOClient.send
This is an unexpected error. Please run

pub --trace upgrade --verbosity=error --no-packages-dir

and include the logs in an issue on https://github.com/dart-lang/pub/issues/new
Error: Unable to pub upgrade flutter tool. Retrying in five seconds...