Update V8 to version 3.31.74 (based on 0a03b5ef188e6d9dfbbed05652eb63d31db2a7da).

TBR=machenbach@chromium.org

Review URL: https://codereview.chromium.org/825663002

Cr-Commit-Position: refs/heads/master@{#309552}

DEPS

@@ -49,7 +49,7 @@ vars = {
   # the commit queue can handle CLs rolling Skia
   # and V8 without interference from each other.
   'v8_branch': 'trunk',
-  'v8_revision': 'c508f35f06a6a2949a8d14006087a6774cea1eac',
+  'v8_revision': 'ed47c2dcd9a30eea73c9cf7b7f120f2d089ad938',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling WebRTC
   # and V8 without interference from each other.