Make clang the default Android compiler.

platform_tools/android/bin/android_setup.sh

 #!/bin/bash
 ###############################################################################
 # Copyright 2015 Google Inc.
 #
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 ###############################################################################
 #
 # android_setup.sh: Sets environment variables used by other Android scripts.
 
 # Fail-fast if anything in the script fails.
 set -e
 
 BUILDTYPE=${BUILDTYPE-Debug}
-USE_CLANG="false"
+USE_CLANG="true"
 
 while (( "$#" )); do
   if [[ "$1" == "-d" ]]; then
     DEVICE_ID=$2
     shift
   elif [[ "$1" == "-i" || "$1" == "--resourcePath" ]]; then
     RESOURCE_PATH=$2
     APP_ARGS=("${APP_ARGS[@]}" "${1}" "${2}")
     shift
   elif [[ "$1" == "-s" ]]; then
@@ skipping 247 matching lines @@
       $ADB $DEVICE_SERIAL shell mkdir -p "$(dirname "$ANDROID_DST")"
       $ADB $DEVICE_SERIAL push $HOST_SRC $ANDROID_DST
     fi
   fi
 
   # turn error checking back on
   set -e
 }
 
 setup_device "${DEVICE_ID}"