Remove content_common from delegate_execute
Remove content_common from delegate_execute

This is not used and entirely dead-code-stripped by the linker (sadly this change doesn't make the binary any smaller).

Review URL: https://codereview.chromium.org/1466423003

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#361398}

axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk