Flip seccomp sandbox back off, now that we have some perf numbers.

git-svn-id: http://src.chromium.org/svn/trunk/src/build@43140 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

common.gypi

@@ -208,9 +208,9 @@
     # Disable TCMalloc's heapchecker.
     'linux_use_heapchecker%': 0,
 
-    # Turn on seccomp sandbox by default.
-    # (Note: this is disabled for official builds.)
-    'linux_use_seccomp_sandbox%': 1,
+    # Set to 1 to turn on seccomp sandbox by default.
+    # (Note: this is ignored for official builds.)
+    'linux_use_seccomp_sandbox%': 0,
 
     # Set to select the Title Case versions of strings in GRD files.
     'use_titlecase_in_grd_files%': 0,