Add the Android SDK to the linux CI and turn on Android tests.

This installs and caches the Android SDK on linux CI
runs. The debug.keystore used to be installed along
with the SDK - but I had to recreate it for the CI.
That directory is cached so it should only run once
or if a layer changes.

The Android tests will now be run in the contrib shard.

In 3531 I maintained the '-a' flag as a way to skip
running Android tests, even now that it is moved to
contrib. I did that because since the OSX CI is not
container based it would have to redownload the entire
SDK each run. So Android tests (and the install-android-sdk
script) are only being run on the Linux CI.

Testing Done:
This is all that is left to land: A travis run with just the RB passed at:
https://travis-ci.org/pantsbuild/pants/builds/116972583

Bugs closed: 10, 937, 2993, 3006, 3012

Reviewed at https://rbcommons.com/s/twitter/r/3538/

.travis.yml

@@ -4,6 +4,13 @@
 # cache configured below.
 sudo: false
 
+# These are needed to run the Android SDK tools.
+addons:
+  apt:
+    packages:
+    - lib32stdc++6
+    - lib32z1
+    - lib32z1-dev
 
 before_cache:
   # Kill all python bytecode in our cached venvs.  Some files appear to
@@ -34,6 +41,8 @@ cache:
     # using its own isolated cache:
     #   https://github.com/pantsbuild/pants/issues/2485
     - $HOME/.npm
+    - $HOME/.android
+    - $SDK_INSTALL_LOCATION
     - build-support/isort.venv
     - build-support/pants_dev_deps.venv
 
@@ -47,6 +56,8 @@ install:
 
 env:
   global:
+    - SDK_INSTALL_LOCATION="$HOME/opt/android-sdk-install"
+    - ANDROID_HOME="$SDK_INSTALL_LOCATION/android-sdk-linux"
     - CXX=g++
     - PANTS_CONFIG_OVERRIDE="['pants.travis-ci.ini']"
     # Credentials for OSX syncing: GH_USER, GH_EMAIL, GH_TOKEN
@@ -60,16 +71,18 @@ env:
     - CI_FLAGS="-cjlpn 'Various pants self checks'"  # (fkmsr)
     - CI_FLAGS="-fkmsrcn -u 0/2 'Unit tests for pants and pants-plugins - shard 1'"  # (jlp)
     - CI_FLAGS="-fkmsrcn -u 1/2 'Unit tests for pants and pants-plugins - shard 2'"
-    - CI_FLAGS="-fkmsrcjlpa 'Python contrib tests'"  # (n)
+    - CI_FLAGS="-fkmsrcjlp 'Python contrib tests'"  # (n)
     - CI_FLAGS="-fkmsrjlpn -i 0/6 'Python integration tests for pants - shard 1'"  # (c)
     - CI_FLAGS="-fkmsrjlpn -i 1/6 'Python integration tests for pants - shard 2'"
     - CI_FLAGS="-fkmsrjlpn -i 2/6 'Python integration tests for pants - shard 3'"
     - CI_FLAGS="-fkmsrjlpn -i 3/6 'Python integration tests for pants - shard 4'"
     - CI_FLAGS="-fkmsrjlpn -i 4/6 'Python integration tests for pants - shard 5'"
     - CI_FLAGS="-fkmsrjlpn -i 5/6 'Python integration tests for pants - shard 6'"
 
+
 before_script: |
   ./build-support/bin/ci-sync.sh
+  ./build-support/bin/install-android-sdk.sh
 
 script: |
   uname -a

build-support/bin/install-android-sdk.sh

@@ -0,0 +1,47 @@
+#!/usr/bin/env bash
+# Copyright 2016 Pants project contributors (see CONTRIBUTORS.md).
+# Licensed under the Apache License, Version 2.0 (see LICENSE).
+
+# Install the Android SDK for the Pants Android contrib module.
+
+# SDK_INSTALL_LOCATION and ANDROID_HOME set in travis.yaml.
+ANDROID_SDK_URL="http://dl.google.com/android/android-sdk_r24.4.1-linux.tgz"
+SDK_FILE=$(basename "$ANDROID_SDK_URL")
+
+# The debug.keystore has a well-known definition and location.
+KEYSTORE_LOCATION="$HOME"/.android
+
+# Add SDKs as needed.
+declare -a SDK_MODULES=(android-19 \
+                        android-20 \
+                        android-21 \
+                        android-22 \
+                        build-tools-19.1.0 \
+                        extra-android-support \
+                        extra-google-m2repository \
+                        extra-android-m2repository \
+                        platform-tools)
+
+mkdir -p "$SDK_INSTALL_LOCATION"
+mkdir -p "$KEYSTORE_LOCATION"
+
+
+function join { local IFS="$1"; shift; echo "$*"; }
+MODULE_LIST=$(join , ${SDK_MODULES[@]})
+
+echo "Downloading $ANDROID_SDK_URL..."
+SDK_ARCHIVE_LOCATION="$SDK_INSTALL_LOCATION"/"$SDK_FILE"
+
+wget -nc "$ANDROID_SDK_URL" -O "$SDK_ARCHIVE_LOCATION"
+tar -C "$SDK_INSTALL_LOCATION" -xf "$SDK_ARCHIVE_LOCATION"
+
+# Spamming 'y' was failing non-deterministically so sleep between echos.
+( sleep 5 && while [ 1 ]; do sleep 1; echo y; done ) | \
+    "$ANDROID_HOME"/tools/android update sdk -u --all --filter "$MODULE_LIST"
+
+# Generate well known debug.keystore if the SDK hasn't created it.
+DEBUG_KEYSTORE="$KEYSTORE_LOCATION"/debug.keystore
+if [[ ! -f "$DEBUG_KEYSTORE" ]]; then
+    keytool -genkey -v -keystore "$KEYSTORE_LOCATION"/debug.keystore -alias androiddebugkey -storepass android  \
+        -keypass android -keyalg RSA -keysize 2048 -validity 10000 -dname "CN=Android Debug,O=Android,C=US"
+fi