Attempt to build with Oboe on Android with Travis

.travis.yml

@@ -36,6 +36,8 @@ install:
         'android-ndk-r21/sysroot/*' \
         'android-ndk-r21/toolchains/arm-linux-androideabi-4.9/prebuilt/linux-x86_64/*' \
         'android-ndk-r21/toolchains/llvm/prebuilt/linux-x86_64/*'
+      export OBOE_LOC=~/oboe
+      git clone --depth 1 -b 1.3-stable https://github.com/google/oboe "$OBOE_LOC"
     fi
 script:
   - >
@@ -54,6 +56,8 @@ script:
       cmake \
         -DANDROID_STL=c++_shared \
         -DCMAKE_TOOLCHAIN_FILE=~/android-ndk-r21/build/cmake/android.toolchain.cmake \
+        -DOBOE_SOURCE="$OBOE_LOC"
+        -DALSOFT_REQUIRE_OBOE=ON \
         -DALSOFT_REQUIRE_OPENSL=ON \
         -DALSOFT_EMBED_HRTF_DATA=YES \
         .