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: refs/heads/master@{#361398}

win8/delegate_execute/delegate_execute.gyp

@@ -44,7 +44,6 @@
         '../../base/base.gyp:base',
         '../../breakpad/breakpad.gyp:breakpad_handler',
         '../../chrome/chrome.gyp:installer_util',
-        '../../content/content.gyp:content_common',
         '../../google_update/google_update.gyp:google_update',
         '../../ui/base/ui_base.gyp:ui_base',
         '../../ui/gfx/gfx.gyp:gfx',