Merge "Switch default execution strategy to racing for developer builds"

function _set_rbe_vars() {

  unset USE_GOMA

  export USE_RBE="true"

  export RBE_CXX_EXEC_STRATEGY="remote_local_fallback"

  export RBE_CXX_EXEC_STRATEGY="racing"

  export RBE_JAVAC_EXEC_STRATEGY="racing"

  export RBE_R8_EXEC_STRATEGY="racing"

  export RBE_D8_EXEC_STRATEGY="racing"

  export RBE_use_unified_cas_ops="true"

  export RBE_JAVAC=1

  export RBE_R8=1