Another attempts

.travis.yml

 matrix:
   include:
-    # Job 1) Analyze the code
-    - os: linux
-      jdk: oraclejdk8
-      sudo: false
-      addons:
-        apt:
-          # Flutter depends on /usr/lib/x86_64-linux-gnu/libstdc++.so.6 version GLIBCXX_3.4.18
-          sources:
-            - ubuntu-toolchain-r-test # if we don't specify this, the libstdc++6 we get is the wrong version
-            - llvm-toolchain-precise # for clang-format-5.0
-          packages:
-            - libstdc++6
-            - fonts-droid
-      before_script:
-        - git clone https://github.com/flutter/flutter.git --depth 1 $HOME/flutter
-        - export PATH=$HOME/flutter/bin:$HOME/flutter/bin/cache/dart-sdk/bin:$PATH
-        - flutter doctor
-        - flutter packages get
-      script:
-        - flutter analyze
-    # Job 2) Check format and run tests
-    - os: linux
-      jdk: oraclejdk8
-      sudo: false
-      addons:
-        apt:
-          # Flutter depends on /usr/lib/x86_64-linux-gnu/libstdc++.so.6 version GLIBCXX_3.4.18
-          sources:
-            - ubuntu-toolchain-r-test # if we don't specify this, the libstdc++6 we get is the wrong version
-            - llvm-toolchain-precise # for clang-format-5.0
-          packages:
-            - libstdc++6
-            - fonts-droid
-            - clang-format-5.0
-      before_script:
-        - git clone https://github.com/flutter/flutter.git --depth 1 $HOME/flutter
-        - export PATH=$HOME/flutter/bin:$HOME/flutter/bin/cache/dart-sdk/bin:$PATH
-        - flutter doctor
-      script:
-        - ./scripts/format_code.sh
-    # Job 3) Build example APKs and run Java tests
     - os: linux
+      env:
+        - SHARD="Build example apks"
       jdk: oraclejdk8
       sudo: false
       addons:
@@ -54,43 +15,19 @@ matrix:
             - libstdc++6
             - fonts-droid
       before_script:
-        - git clone https://github.com/flutter/flutter.git --depth 1 $HOME/flutter
+        - ./scripts/before_build_apks.sh
+        - export ANDROID_HOME=`$HOME/android-sdk
         - export PATH=$HOME/flutter/bin:$HOME/flutter/bin/cache/dart-sdk/bin:$PATH
-        - wget https://dl.google.com/android/repository/sdk-tools-linux-3859397.zip
-        - mkdir $HOME/android-sdk
-        - unzip -qq sdk-tools-linux-3859397.zip -d $HOME/android-sdk
-        - export ANDROID_HOME=$HOME/android-sdk
-        - export PATH=$HOME/android-sdk/tools/bin:$PATH
-        - mkdir -p /home/travis/.android # silence sdkmanager warning
-        - echo 'count=0' > /home/travis/.android/repositories.cfg # silence sdkmanager warning
-        - echo y | sdkmanager "tools"
-        - echo y | sdkmanager "platform-tools"
-        - echo y | sdkmanager "build-tools;25.0.3"
-        - echo y | sdkmanager "platforms;android-25"
-        - echo y | sdkmanager "extras;android;m2repository"
-        - echo y | sdkmanager "extras;google;m2repository"
-        - echo y | sdkmanager "patcher;v4"
-        - sdkmanager --list
-        - wget http://services.gradle.org/distributions/gradle-3.5-bin.zip
-        - mkdir $HOME/gradle-3.5
-        - unzip -qq gradle-3.5-bin.zip -d $HOME/gradle-3.5
-        - export GRADLE_HOME=$HOME/gradle-3.5
-        - export PATH=$GRADLE_HOME/bin:$PATH
-        - gradle -v
-        - flutter doctor
       script:
         - flutter build apk
-    # Job 4) Build example IPAs
+    # Job 2) Build example IPAs
     - os: osx
+      env:
+        - SHARD="Build example ipas"
       language: generic
       osx_image: xcode9.3
       before_script:
-        - pip2 install six
-        - brew update
-        - brew install libimobiledevice
-        - brew install ideviceinstaller
-        - brew install ios-deploy
-        - git clone https://github.com/flutter/flutter.git --depth 1 $HOME/flutter
+        - ./scripts/before_build_ipas.sh
         - export PATH=$HOME/flutter/bin:$HOME/flutter/bin/cache/dart-sdk/bin:$PATH
       script:
         - flutter build ios --no-codesign

scripts/before_build_apks.sh

+#!/bin/bash
+wget https://dl.google.com/android/repository/sdk-tools-linux-3859397.zip
+mkdir android-sdk
+unzip -qq sdk-tools-linux-3859397.zip -d $HOME/android-sdk
+export ANDROID_HOME=$HOME/android-sdk
+export PATH=$HOME/android-sdk/tools/bin:$PATH
+mkdir -p /home/travis/.android # silence sdkmanager warning
+echo 'count=0' > /home/travis/.android/repositories.cfg # silence sdkmanager warning
+        # suppressing output of sdkmanager to keep log under 4MB (travis limit)
+echo y | sdkmanager "tools" >/dev/null
+echo y | sdkmanager "platform-tools" >/dev/null
+echo y | sdkmanager "build-tools;26.0.3" >/dev/null
+echo y | sdkmanager "platforms;android-26" >/dev/null
+echo y | sdkmanager "extras;android;m2repository" >/dev/null
+echo y | sdkmanager "extras;google;m2repository" >/dev/null
+echo y | sdkmanager "patcher;v4" >/dev/null
+sdkmanager --list
+wget http://services.gradle.org/distributions/gradle-4.1-bin.zip
+unzip -qq gradle-4.1-bin.zip -d $HOME/gradle-4.1
+export GRADLE_HOME=$HOME/gradle-4.1
+export PATH=$GRADLE_HOME/bin:$PATH
+gradle -v
+git clone https://github.com/flutter/flutter.git $HOME/flutter
+export PATH=$HOME/flutter/bin:$HOME/flutter/bin/cache/dart-sdk/bin:$PATH
+flutter doctor
+

scripts/before_ipas.sh

+#!/bin/bash
+brew update
+brew install libimobiledevice
+brew install ideviceinstaller
+brew install ios-deploy
+pod repo update
+gem update cocoapods
+git clone https://github.com/flutter/flutter.git $HOME/flutter
+export PATH=$HOME/flutter/bin:$HOME/flutter/bin/cache/dart-sdk/bin:$PATH
+flutter doctor

scripts/build.sh

-#!/bin/bash
-
-set -e
-
-cd ../example
-
-if [[ $1 == 'apk' ]]; then
-    flutter build apk
-elif [[ $1 == 'ios' ]]; then
-    flutter build ios --no-codesign
-else
-    echo "Neither 'apk' or 'ios' were specified, so not building"
-fi

scripts/format_code.sh

-#!/bin/bash
-
-set -e
-
-# Format Dart code
-printf 'Formatting Dart code\n'
-flutter format .
-printf '\n'
-
-# Format Objective-C code
-printf 'Formatting Objective-C code\n'
-find . \( -name '*.h' -o -name '*.m' \) -exec clang-format -i -style=Google '{}' \;
-printf '\n'
-
-# Format Java code
-printf 'Formatting JAVA code\n'
-find . \( -name '*.java' \) -exec java -jar ./scripts/utils/google-java-format-1.3-all-deps.jar --replace '{}' \;
-printf '\n'
-
-modified_files=$(git ls-files --modified)
-if [[ $modified_files ]]; then
-    printf 'These files are not formatted correctly:\n'
-    printf '\n'
-    echo $modified_files | tr ' ' '\n'
-    exit 1
-else
-    printf "All files are formatted correctly"
-    exit 0
-fi