Disable goma/ccache with USE_XXX=false

# limitations under the License.

#

ifneq ($(USE_CCACHE),)

ifneq ($(filter-out false,$(USE_CCACHE)),)

  # The default check uses size and modification time, causing false misses

  # since the mtime depends when the repo was checked out

  export CCACHE_COMPILERCHECK := content

#

# Notice: this works only with Google's Goma build infrastructure.

ifneq ($(USE_GOMA),)

ifneq ($(filter-out false,$(USE_GOMA)),)

  # Check if USE_NINJA is not false because GNU make won't work well

  # with goma. Note this file is evaluated twice, once by GNU make and

  # once by kati with USE_NINJA=false. We do this check in the former