Auto merge of #188 - servo:jdm-patch-11, r=asajeffrey

Fix macOS TravisCI builds

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Author: bors-servo

.travis.yml

@@ -21,17 +21,22 @@ addons:
       - g++-6
       - clang-5.0
   homebrew:
+    update: true
     packages:
       - python
       - python@2
+      - [email protected]
+      - ccache
+      - llvm
+      - yasm
 
 env:
   - FEATURES=""
   - FEATURES="--features debugmozjs"
 
 before_script:
   - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then export CC=gcc-6; export CXX=g++-6; fi
-  - if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then brew update; brew install [email protected] ccache llvm yasm; fi
+  - if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then export PYTHON3="/usr/local/opt/python/bin/python3"; fi
 
 script:
   - ccache -z