Update V8 DEPS.

Rolling v8/tools/clang to 4b5142322face2df2374a246dba98ae82be317b0

TBR=machenbach@chromium.org

Review URL: https://codereview.chromium.org/872893010

Cr-Commit-Position: refs/heads/master@{#26543}

DEPS

@@ -18,7 +18,7 @@ deps = {
   "v8/testing/gmock":
     Var("git_url") + "/external/googlemock.git" + "@" + "29763965ab52f24565299976b936d1265cb6a271",  # from svn revision 501
   "v8/tools/clang":
-    Var("git_url") + "/chromium/src/tools/clang.git" + "@" + "5489bbf01a5292a6c44d4cad7875ba2cb4ac975b",
+    Var("git_url") + "/chromium/src/tools/clang.git" + "@" + "4b5142322face2df2374a246dba98ae82be317b0",
 }
 
 deps_os = {