Allow rebuilding of docker image, re-enable deploy gallery macos (#43362)

diff --git a/.cirrus.yml b/.cirrus.yml
index 8ec0a8a..b5e0d8a 100644
--- a/.cirrus.yml
+++ b/.cirrus.yml
@@ -22,7 +22,7 @@
 # LINUX SHARDS
 task:
   container:
-    image: gcr.io/flutter-cirrus/build-flutter-image:latest
+    dockerfile: "dev/ci/docker_linux/Dockerfile"
     cpu: $CPU
     memory: $MEMORY
   environment:
@@ -34,6 +34,7 @@
     CPU: 1 # 0.1-8 without compute credits, 0.1-30 with (yes, you can go fractional)
     MEMORY: 4G # 256M-24G without compute credits, 256M-90G with
     CIRRUS_WORKING_DIR: "/tmp/$FLUTTER_SDK_PATH_WITH_SPACE"
+    CIRRUS_DOCKER_CONTEXT: "dev/ci/docker_linux"
     PATH: "$CIRRUS_WORKING_DIR/bin:$CIRRUS_WORKING_DIR/bin/cache/dart-sdk/bin:$PATH"
     ANDROID_SDK_ROOT: "/opt/android_sdk"
   pub_cache:
@@ -442,8 +443,8 @@
   setup_script:
     - date
     - which flutter
-    - sudo gem install cocoapods
-    - sudo gem install xcpretty
+    - sudo gem install bundler -v 2.0.2 -N
+    - bundle install --system --gemfile=dev/ci/mac/Gemfile
     - git clean -xffd
     - git fetch origin
     - git fetch origin master # To set FETCH_HEAD, so that "git merge-base" works.
@@ -575,7 +576,10 @@
         - ./dev/bots/deploy_gallery.sh
 
 docker_builder:
-  # Only build a new docker image when we tag a release (for dev, beta, or release.)
+  # Only build a new docker image when we tag a release (for dev, beta, or
+  # release.) Note: tagging a commit and pushing to a release branch are
+  # different cirrus triggers. See a tag CI run at e.g.
+  # https://cirrus-ci.com/github/flutter/flutter/v1.2.3
   only_if: $CIRRUS_TAG != ''
   environment:
     GCLOUD_CREDENTIALS: ENCRYPTED[f7c098d4dd7f5ee1bfee0bb7e944cce72efbe10e97ad6440ae72de4de6a1c24d23f421a2619c668e94377fb64b0bb3e6]
@@ -594,7 +598,8 @@
     - hostonly_devicelab_tests-2-linux
     - hostonly_devicelab_tests-3_last-linux
     - firebase_test_lab_tests-linux
-  script:
-    - "$CIRRUS_WORKING_DIR/dev/ci/docker_linux/docker_build.sh"
-    - "$CIRRUS_WORKING_DIR/dev/ci/docker_linux/docker_login.sh"
-    - "$CIRRUS_WORKING_DIR/dev/ci/docker_linux/docker_push.sh"
+  build_script:
+    - cd "$CIRRUS_WORKING_DIR/dev/ci/docker_linux"
+    - ./docker_build.sh
+    - ./docker_login.sh
+    - ./docker_push.sh
diff --git a/.gitignore b/.gitignore
index 4946cd9..f6d4952 100644
--- a/.gitignore
+++ b/.gitignore
@@ -98,3 +98,4 @@
 !**/ios/**/default.pbxuser
 !**/ios/**/default.perspectivev3
 !/packages/flutter_tools/test/data/dart_dependencies_test/**/.packages
+!/dev/ci/**/Gemfile.lock
diff --git a/dev/bots/deploy_gallery.sh b/dev/bots/deploy_gallery.sh
index d0740e8..86d34d9 100755
--- a/dev/bots/deploy_gallery.sh
+++ b/dev/bots/deploy_gallery.sh
@@ -99,8 +99,7 @@
       echo "Testing archiving with distribution profile..."
       (
         cd examples/flutter_gallery/ios
-        # TODO(fujino) re-enable after resolving https://github.com/flutter/flutter/issues/43204
-        #fastlane build_and_deploy_testflight
+        fastlane build_and_deploy_testflight
       )
       echo "(Not deploying; Flutter Gallery is only deployed to TestFlight for tagged dev branch commits.)"
     fi
diff --git a/dev/ci/docker_linux/Dockerfile b/dev/ci/docker_linux/Dockerfile
index 59dbefb..551b630 100644
--- a/dev/ci/docker_linux/Dockerfile
+++ b/dev/ci/docker_linux/Dockerfile
@@ -10,6 +10,8 @@
 # for performing pushes to production, and so this image is quite a bit larger
 # than strictly needed for just building Flutter apps.
 
+# Note: updating past stretch (Debian 9) will bump Java past version 8,
+# which will break the Android SDK.
 FROM debian:stretch
 MAINTAINER Flutter Developers <flutter-dev@googlegroups.com>
 
@@ -51,7 +53,7 @@
 # Install the rest of the dependencies.
 RUN apt-get install -y --no-install-recommends \
   locales \
-  golang \
+  gcc \
   ruby \
   ruby-dev \
   nodejs \
@@ -108,23 +110,24 @@
 COPY patch_firebase.sh /root/patch_firebase.sh
 RUN /root/patch_firebase.sh
 
+# Install golang more recent than in repo (necessary for dashing to build)
+RUN curl 'https://dl.google.com/go/go1.13.3.linux-amd64.tar.gz' | tar xvz
+ENV GOBINARY=/go/bin/go
+
 # Install dashing
-# This is why we need golang installed.
 RUN mkdir -p /opt/gopath/bin
 ENV GOPATH=/opt/gopath
 ENV PATH="${GOPATH}/bin:${PATH}"
-RUN go get -u github.com/technosophos/dashing
+RUN $GOBINARY get -u github.com/technosophos/dashing
 
 # Set locale to en_US
 RUN locale-gen en_US "en_US.UTF-8" && dpkg-reconfigure locales
 ENV LANG en_US.UTF-8
 
-# Install coveralls and Firebase
-# This is why we need ruby installed.
 # Skip all the documentation (-N) since it's just on CI.
-RUN gem install coveralls -N
 RUN gem install bundler -N
-# Install fastlane which is used on Linux to build and deploy Android
-# builds to the Play Store.
-RUN gem install fastlane -N
 
+COPY Gemfile /Gemfile
+COPY Gemfile.lock /Gemfile.lock
+
+RUN bundle install --system
diff --git a/dev/ci/docker_linux/Gemfile b/dev/ci/docker_linux/Gemfile
new file mode 100644
index 0000000..9b041f8
--- /dev/null
+++ b/dev/ci/docker_linux/Gemfile
@@ -0,0 +1,5 @@
+source "https://rubygems.org"
+
+# Install fastlane which is used on Linux to build and deploy Android
+# builds to the Play Store.
+gem 'fastlane', '2.134.0'
diff --git a/dev/ci/docker_linux/Gemfile.lock b/dev/ci/docker_linux/Gemfile.lock
new file mode 100644
index 0000000..b3085a2
--- /dev/null
+++ b/dev/ci/docker_linux/Gemfile.lock
@@ -0,0 +1,159 @@
+GEM
+  remote: https://rubygems.org/
+  specs:
+    CFPropertyList (3.0.1)
+    addressable (2.7.0)
+      public_suffix (>= 2.0.2, < 5.0)
+    atomos (0.1.3)
+    babosa (1.0.3)
+    claide (1.0.3)
+    colored (1.2)
+    colored2 (3.1.2)
+    commander-fastlane (4.4.6)
+      highline (~> 1.7.2)
+    declarative (0.0.10)
+    declarative-option (0.1.0)
+    digest-crc (0.4.1)
+    domain_name (0.5.20190701)
+      unf (>= 0.0.5, < 1.0.0)
+    dotenv (2.7.5)
+    emoji_regex (1.0.1)
+    excon (0.67.0)
+    faraday (0.17.0)
+      multipart-post (>= 1.2, < 3)
+    faraday-cookie_jar (0.0.6)
+      faraday (>= 0.7.4)
+      http-cookie (~> 1.0.0)
+    faraday_middleware (0.13.1)
+      faraday (>= 0.7.4, < 1.0)
+    fastimage (2.1.7)
+    fastlane (2.134.0)
+      CFPropertyList (>= 2.3, < 4.0.0)
+      addressable (>= 2.3, < 3.0.0)
+      babosa (>= 1.0.2, < 2.0.0)
+      bundler (>= 1.12.0, < 3.0.0)
+      colored
+      commander-fastlane (>= 4.4.6, < 5.0.0)
+      dotenv (>= 2.1.1, < 3.0.0)
+      emoji_regex (>= 0.1, < 2.0)
+      excon (>= 0.45.0, < 1.0.0)
+      faraday (~> 0.17)
+      faraday-cookie_jar (~> 0.0.6)
+      faraday_middleware (~> 0.13.1)
+      fastimage (>= 2.1.0, < 3.0.0)
+      gh_inspector (>= 1.1.2, < 2.0.0)
+      google-api-client (>= 0.21.2, < 0.24.0)
+      google-cloud-storage (>= 1.15.0, < 2.0.0)
+      highline (>= 1.7.2, < 2.0.0)
+      json (< 3.0.0)
+      jwt (~> 2.1.0)
+      mini_magick (>= 4.9.4, < 5.0.0)
+      multi_xml (~> 0.5)
+      multipart-post (~> 2.0.0)
+      plist (>= 3.1.0, < 4.0.0)
+      public_suffix (~> 2.0.0)
+      rubyzip (>= 1.3.0, < 2.0.0)
+      security (= 0.1.3)
+      simctl (~> 1.6.3)
+      slack-notifier (>= 2.0.0, < 3.0.0)
+      terminal-notifier (>= 2.0.0, < 3.0.0)
+      terminal-table (>= 1.4.5, < 2.0.0)
+      tty-screen (>= 0.6.3, < 1.0.0)
+      tty-spinner (>= 0.8.0, < 1.0.0)
+      word_wrap (~> 1.0.0)
+      xcodeproj (>= 1.8.1, < 2.0.0)
+      xcpretty (~> 0.3.0)
+      xcpretty-travis-formatter (>= 0.0.3)
+    gh_inspector (1.1.3)
+    google-api-client (0.23.9)
+      addressable (~> 2.5, >= 2.5.1)
+      googleauth (>= 0.5, < 0.7.0)
+      httpclient (>= 2.8.1, < 3.0)
+      mime-types (~> 3.0)
+      representable (~> 3.0)
+      retriable (>= 2.0, < 4.0)
+      signet (~> 0.9)
+    google-cloud-core (1.3.2)
+      google-cloud-env (~> 1.0)
+    google-cloud-env (1.2.1)
+      faraday (~> 0.11)
+    google-cloud-storage (1.16.0)
+      digest-crc (~> 0.4)
+      google-api-client (~> 0.23)
+      google-cloud-core (~> 1.2)
+      googleauth (>= 0.6.2, < 0.10.0)
+    googleauth (0.6.7)
+      faraday (~> 0.12)
+      jwt (>= 1.4, < 3.0)
+      memoist (~> 0.16)
+      multi_json (~> 1.11)
+      os (>= 0.9, < 2.0)
+      signet (~> 0.7)
+    highline (1.7.10)
+    http-cookie (1.0.3)
+      domain_name (~> 0.5)
+    httpclient (2.8.3)
+    json (2.2.0)
+    jwt (2.1.0)
+    memoist (0.16.0)
+    mime-types (3.3)
+      mime-types-data (~> 3.2015)
+    mime-types-data (3.2019.1009)
+    mini_magick (4.9.5)
+    multi_json (1.14.1)
+    multi_xml (0.6.0)
+    multipart-post (2.0.0)
+    nanaimo (0.2.6)
+    naturally (2.2.0)
+    os (1.0.1)
+    plist (3.5.0)
+    public_suffix (2.0.5)
+    representable (3.0.4)
+      declarative (< 0.1.0)
+      declarative-option (< 0.2.0)
+      uber (< 0.2.0)
+    retriable (3.1.2)
+    rouge (2.0.7)
+    rubyzip (1.3.0)
+    security (0.1.3)
+    signet (0.11.0)
+      addressable (~> 2.3)
+      faraday (~> 0.9)
+      jwt (>= 1.5, < 3.0)
+      multi_json (~> 1.10)
+    simctl (1.6.6)
+      CFPropertyList
+      naturally
+    slack-notifier (2.3.2)
+    terminal-notifier (2.0.0)
+    terminal-table (1.8.0)
+      unicode-display_width (~> 1.1, >= 1.1.1)
+    tty-cursor (0.7.0)
+    tty-screen (0.7.0)
+    tty-spinner (0.9.1)
+      tty-cursor (~> 0.7)
+    uber (0.1.0)
+    unf (0.1.4)
+      unf_ext
+    unf_ext (0.0.7.6)
+    unicode-display_width (1.6.0)
+    word_wrap (1.0.0)
+    xcodeproj (1.13.0)
+      CFPropertyList (>= 2.3.3, < 4.0)
+      atomos (~> 0.1.3)
+      claide (>= 1.0.2, < 2.0)
+      colored2 (~> 3.1)
+      nanaimo (~> 0.2.6)
+    xcpretty (0.3.0)
+      rouge (~> 2.0.7)
+    xcpretty-travis-formatter (1.0.0)
+      xcpretty (~> 0.2, >= 0.0.7)
+
+PLATFORMS
+  ruby
+
+DEPENDENCIES
+  fastlane
+
+BUNDLED WITH
+  2.0.2
diff --git a/dev/ci/mac/Gemfile b/dev/ci/mac/Gemfile
new file mode 100644
index 0000000..f7c2209
--- /dev/null
+++ b/dev/ci/mac/Gemfile
@@ -0,0 +1,11 @@
+# This Gemfile is for the setup step of the Cirrus Mac tasks
+source 'https://rubygems.org'
+
+# If fastlane fails with a wrong Google Cloud dependency, bump this version,
+# e.g. https://github.com/flutter/flutter/pull/43362
+gem 'fastlane', '2.134.0'
+gem 'xcpretty', '0.3.0'
+
+# Don't pin cocoapods so we can catch breakages from upstream changes, e.g.
+# https://github.com/flutter/flutter/issues/41144
+gem 'cocoapods'
diff --git a/dev/ci/mac/Gemfile.lock b/dev/ci/mac/Gemfile.lock
new file mode 100644
index 0000000..0ab9b30
--- /dev/null
+++ b/dev/ci/mac/Gemfile.lock
@@ -0,0 +1,215 @@
+GEM
+  remote: https://rubygems.org/
+  specs:
+    CFPropertyList (3.0.1)
+    activesupport (4.2.11.1)
+      i18n (~> 0.7)
+      minitest (~> 5.1)
+      thread_safe (~> 0.3, >= 0.3.4)
+      tzinfo (~> 1.1)
+    addressable (2.7.0)
+      public_suffix (>= 2.0.2, < 5.0)
+    algoliasearch (1.27.1)
+      httpclient (~> 2.8, >= 2.8.3)
+      json (>= 1.5.1)
+    atomos (0.1.3)
+    babosa (1.0.3)
+    claide (1.0.3)
+    cocoapods (1.8.4)
+      activesupport (>= 4.0.2, < 5)
+      claide (>= 1.0.2, < 2.0)
+      cocoapods-core (= 1.8.4)
+      cocoapods-deintegrate (>= 1.0.3, < 2.0)
+      cocoapods-downloader (>= 1.2.2, < 2.0)
+      cocoapods-plugins (>= 1.0.0, < 2.0)
+      cocoapods-search (>= 1.0.0, < 2.0)
+      cocoapods-stats (>= 1.0.0, < 2.0)
+      cocoapods-trunk (>= 1.4.0, < 2.0)
+      cocoapods-try (>= 1.1.0, < 2.0)
+      colored2 (~> 3.1)
+      escape (~> 0.0.4)
+      fourflusher (>= 2.3.0, < 3.0)
+      gh_inspector (~> 1.0)
+      molinillo (~> 0.6.6)
+      nap (~> 1.0)
+      ruby-macho (~> 1.4)
+      xcodeproj (>= 1.11.1, < 2.0)
+    cocoapods-core (1.8.4)
+      activesupport (>= 4.0.2, < 6)
+      algoliasearch (~> 1.0)
+      concurrent-ruby (~> 1.1)
+      fuzzy_match (~> 2.0.4)
+      nap (~> 1.0)
+    cocoapods-deintegrate (1.0.4)
+    cocoapods-downloader (1.2.2)
+    cocoapods-plugins (1.0.0)
+      nap
+    cocoapods-search (1.0.0)
+    cocoapods-stats (1.1.0)
+    cocoapods-trunk (1.4.1)
+      nap (>= 0.8, < 2.0)
+      netrc (~> 0.11)
+    cocoapods-try (1.1.0)
+    colored (1.2)
+    colored2 (3.1.2)
+    commander-fastlane (4.4.6)
+      highline (~> 1.7.2)
+    concurrent-ruby (1.1.5)
+    declarative (0.0.10)
+    declarative-option (0.1.0)
+    digest-crc (0.4.1)
+    domain_name (0.5.20190701)
+      unf (>= 0.0.5, < 1.0.0)
+    dotenv (2.7.5)
+    emoji_regex (1.0.1)
+    escape (0.0.4)
+    excon (0.67.0)
+    faraday (0.17.0)
+      multipart-post (>= 1.2, < 3)
+    faraday-cookie_jar (0.0.6)
+      faraday (>= 0.7.4)
+      http-cookie (~> 1.0.0)
+    faraday_middleware (0.13.1)
+      faraday (>= 0.7.4, < 1.0)
+    fastimage (2.1.7)
+    fastlane (2.134.0)
+      CFPropertyList (>= 2.3, < 4.0.0)
+      addressable (>= 2.3, < 3.0.0)
+      babosa (>= 1.0.2, < 2.0.0)
+      bundler (>= 1.12.0, < 3.0.0)
+      colored
+      commander-fastlane (>= 4.4.6, < 5.0.0)
+      dotenv (>= 2.1.1, < 3.0.0)
+      emoji_regex (>= 0.1, < 2.0)
+      excon (>= 0.45.0, < 1.0.0)
+      faraday (~> 0.17)
+      faraday-cookie_jar (~> 0.0.6)
+      faraday_middleware (~> 0.13.1)
+      fastimage (>= 2.1.0, < 3.0.0)
+      gh_inspector (>= 1.1.2, < 2.0.0)
+      google-api-client (>= 0.21.2, < 0.24.0)
+      google-cloud-storage (>= 1.15.0, < 2.0.0)
+      highline (>= 1.7.2, < 2.0.0)
+      json (< 3.0.0)
+      jwt (~> 2.1.0)
+      mini_magick (>= 4.9.4, < 5.0.0)
+      multi_xml (~> 0.5)
+      multipart-post (~> 2.0.0)
+      plist (>= 3.1.0, < 4.0.0)
+      public_suffix (~> 2.0.0)
+      rubyzip (>= 1.3.0, < 2.0.0)
+      security (= 0.1.3)
+      simctl (~> 1.6.3)
+      slack-notifier (>= 2.0.0, < 3.0.0)
+      terminal-notifier (>= 2.0.0, < 3.0.0)
+      terminal-table (>= 1.4.5, < 2.0.0)
+      tty-screen (>= 0.6.3, < 1.0.0)
+      tty-spinner (>= 0.8.0, < 1.0.0)
+      word_wrap (~> 1.0.0)
+      xcodeproj (>= 1.8.1, < 2.0.0)
+      xcpretty (~> 0.3.0)
+      xcpretty-travis-formatter (>= 0.0.3)
+    fourflusher (2.3.1)
+    fuzzy_match (2.0.4)
+    gh_inspector (1.1.3)
+    google-api-client (0.23.9)
+      addressable (~> 2.5, >= 2.5.1)
+      googleauth (>= 0.5, < 0.7.0)
+      httpclient (>= 2.8.1, < 3.0)
+      mime-types (~> 3.0)
+      representable (~> 3.0)
+      retriable (>= 2.0, < 4.0)
+      signet (~> 0.9)
+    google-cloud-core (1.3.2)
+      google-cloud-env (~> 1.0)
+    google-cloud-env (1.2.1)
+      faraday (~> 0.11)
+    google-cloud-storage (1.16.0)
+      digest-crc (~> 0.4)
+      google-api-client (~> 0.23)
+      google-cloud-core (~> 1.2)
+      googleauth (>= 0.6.2, < 0.10.0)
+    googleauth (0.6.7)
+      faraday (~> 0.12)
+      jwt (>= 1.4, < 3.0)
+      memoist (~> 0.16)
+      multi_json (~> 1.11)
+      os (>= 0.9, < 2.0)
+      signet (~> 0.7)
+    highline (1.7.10)
+    http-cookie (1.0.3)
+      domain_name (~> 0.5)
+    httpclient (2.8.3)
+    i18n (0.9.5)
+      concurrent-ruby (~> 1.0)
+    json (2.2.0)
+    jwt (2.1.0)
+    memoist (0.16.0)
+    mime-types (3.3)
+      mime-types-data (~> 3.2015)
+    mime-types-data (3.2019.1009)
+    mini_magick (4.9.5)
+    minitest (5.12.2)
+    molinillo (0.6.6)
+    multi_json (1.14.1)
+    multi_xml (0.6.0)
+    multipart-post (2.0.0)
+    nanaimo (0.2.6)
+    nap (1.1.0)
+    naturally (2.2.0)
+    netrc (0.11.0)
+    os (1.0.1)
+    plist (3.5.0)
+    public_suffix (2.0.5)
+    representable (3.0.4)
+      declarative (< 0.1.0)
+      declarative-option (< 0.2.0)
+      uber (< 0.2.0)
+    retriable (3.1.2)
+    rouge (2.0.7)
+    ruby-macho (1.4.0)
+    rubyzip (1.3.0)
+    security (0.1.3)
+    signet (0.11.0)
+      addressable (~> 2.3)
+      faraday (~> 0.9)
+      jwt (>= 1.5, < 3.0)
+      multi_json (~> 1.10)
+    simctl (1.6.6)
+      CFPropertyList
+      naturally
+    slack-notifier (2.3.2)
+    terminal-notifier (2.0.0)
+    terminal-table (1.8.0)
+      unicode-display_width (~> 1.1, >= 1.1.1)
+    thread_safe (0.3.6)
+    tty-cursor (0.7.0)
+    tty-screen (0.7.0)
+    tty-spinner (0.9.1)
+      tty-cursor (~> 0.7)
+    tzinfo (1.2.5)
+      thread_safe (~> 0.1)
+    uber (0.1.0)
+    unf (0.1.4)
+      unf_ext
+    unf_ext (0.0.7.6)
+    unicode-display_width (1.6.0)
+    word_wrap (1.0.0)
+    xcodeproj (1.13.0)
+      CFPropertyList (>= 2.3.3, < 4.0)
+      atomos (~> 0.1.3)
+      claide (>= 1.0.2, < 2.0)
+      colored2 (~> 3.1)
+      nanaimo (~> 0.2.6)
+    xcpretty (0.3.0)
+      rouge (~> 2.0.7)
+    xcpretty-travis-formatter (1.0.0)
+      xcpretty (~> 0.2, >= 0.0.7)
+PLATFORMS
+  ruby
+DEPENDENCIES
+  cocoapods
+  fastlane (= 2.134.0)
+  xcpretty (= 0.3.0)
+BUNDLED WITH
+  2.0.2