Revert of Add mock context and use in ResourceCacheTest. (patchset #4 id:60001 of https://codereview.chromium.org/702083003/) Reason for revert: Breaking tests Original issue's description: > Add mock context and use in ResourceCacheTest. > > BUG=skia:2889 > > Committed: https://skia.googlesource.com/skia/+/820dd6c335411aad889c1d7e8a857642ecd87e30 TBR=robertphillips@google.com NOTREECHECKS=true NOTRY=true BUG=skia:2889 Review URL: https://codereview.chromium.org/704563004