Try to add build_android task back to travis. (#8699)

.travis.yml

@@ -4,13 +4,17 @@ cache:
     - $HOME/.ccache
     - $HOME/.cache/pip
     - $TRAVIS_BUILD_DIR/build/third_party
+    - $TRAVIS_BUILD_DIR/build_android/third_party
 sudo: required
 dist: trusty
+services:
+  - docker
 os:
   - linux
 env:
   - JOB=build_doc
   - JOB=check_style
+  - JOB=build_android
 addons:
   apt:
     packages:
@@ -41,8 +45,10 @@ before_install:
     function timeout() { perl -e 'alarm shift; exec @ARGV' "$@"; }
 script:
   - |
-    timeout 2580 paddle/scripts/travis/${JOB}.sh # 43min timeout
-    RESULT=$?; if [ $RESULT -eq 0 ] || [ $RESULT -eq 142 ]; then true ;else exit 1; fi;
+    # 43min timeout
+    if [[ "$JOB" == "build_android" ]]; then timeout 2580 docker run -it --rm -v "$TRAVIS_BUILD_DIR:/paddle" paddlepaddle/paddle:latest-dev-android;
+    else timeout 2580 paddle/scripts/travis/${JOB}.sh; fi;
+    RESULT=$?; if [ $RESULT -eq 0 ] || [ $RESULT -eq 142 ]; then true; else exit 1; fi;
   - |
     if [[ "$JOB" != "build_doc" ]]; then exit 0; fi;
     if [[ "$TRAVIS_PULL_REQUEST" != "false" ]]; then exit 0; fi;

CMakeLists.txt

@@ -168,7 +168,7 @@ include_directories("${CMAKE_CURRENT_BINARY_DIR}/go/pserver/client/c")
 set(EXTERNAL_LIBS
     gflags
     glog
-    cblas
+    ${CBLAS_LIBRARIES}
     protobuf
     zlib
     ${PYTHON_LIBRARIES}

paddle/scripts/docker/build_android.sh

@@ -31,7 +31,6 @@ ${ANDROID_NDK_HOME}/build/tools/make-standalone-toolchain.sh \
 BUILD_ROOT=/paddle/build_android
 DEST_ROOT=/paddle/install_android
 
-rm -rf $BUILD_ROOT 2>/dev/null || true
 mkdir -p $BUILD_ROOT
 cd $BUILD_ROOT