[DevTools] Fix standalone V8 Inspector build

R=dgozman@chromium.org
BUG=

Review-Url: https://codereview.chromium.org/2269803002
Cr-Original-Commit-Position: refs/heads/master@{#413610}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: 47e6601eb43729f0e1628ab0004b0e394c8e6f6e
1 file changed