Reduce GPU mailbox size to 16 bytes

cc/ipc/cc_param_traits_unittest.cc

Index: cc/ipc/cc_param_traits_unittest.cc
diff --git a/cc/ipc/cc_param_traits_unittest.cc b/cc/ipc/cc_param_traits_unittest.cc
index 6bb3c302244043de54bf2ae94057534cb31ff184..4590c8b64218b0a3efdba9f163487ea418034e38 100644
--- a/cc/ipc/cc_param_traits_unittest.cc
+++ b/cc/ipc/cc_param_traits_unittest.cc
@@ -563,14 +563,10 @@ TEST_F(CCParamTraitsTest, Resources) {
   arbitrary_token2.SetVerifyFlush();
 
   GLbyte arbitrary_mailbox1[GL_MAILBOX_SIZE_CHROMIUM] = {
-      1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 1, 2,
-      3, 4, 5, 6, 7, 8, 9, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 1, 2, 3, 4,
-      5, 6, 7, 8, 9, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 1, 2, 3, 4};
+      1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 1, 2, 3, 4, 5, 6};
 
   GLbyte arbitrary_mailbox2[GL_MAILBOX_SIZE_CHROMIUM] = {
-      0, 9, 8, 7, 6, 5, 4, 3, 2, 1, 9, 7, 5, 3, 1, 2, 4, 6, 8, 0, 0, 9,
-      8, 7, 6, 5, 4, 3, 2, 1, 9, 7, 5, 3, 1, 2, 4, 6, 8, 0, 0, 9, 8, 7,
-      6, 5, 4, 3, 2, 1, 9, 7, 5, 3, 1, 2, 4, 6, 8, 0, 0, 9, 8, 7};
+      0, 9, 8, 7, 6, 5, 4, 3, 2, 1, 9, 7, 5, 3, 1, 2};
 
   TransferableResource arbitrary_resource1;
   arbitrary_resource1.id = 2178312;