ios: Fixing base_unittests to build with gn.

build/secondary/third_party/nss/BUILD.gn

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import("//build/config/linux/pkg_config.gni")
 
 if (is_linux) {
   # This is a dependency on NSS with no libssl. On Linux we use a built-in SSL
   # library but the system NSS libraries. Non-Linux platforms using NSS use the
   # hermetic one in //third_party/nss.
@@ skipping 1078 matching lines @@
         "nss/lib/libpkix/pkix_pl_nss/system",
       ]
     } else {
       defines += [ "NSS_DISABLE_LIBPKIX" ]
     }
 
     if (!include_nss_root_certs) {
       defines += [ "NSS_DISABLE_ROOT_CERTS" ]
     }
 
-    if (current_cpu == "x64" && !is_win) {
+    if (current_cpu == "x64" && !is_win && !is_ios) {
       sources -= [
         "nss/lib/freebl/chacha20/chacha20.c",
         "nss/lib/freebl/poly1305/poly1305.c",
       ]
     } else {
       sources -= [
         "nss/lib/freebl/chacha20/chacha20_vec.c",
         "nss/lib/freebl/poly1305/poly1305-donna-x64-sse2-incremental-source.c",
       ]
     }
@@ skipping 60 matching lines @@
           "MP_IS_LITTLE_ENDIAN",
           "WIN64",
         ]
       }
     } else {
       # Not Windows.
       sources -= [
         # mpi_x86_asm.c contains MSVC inline assembly code.
         "nss/lib/freebl/mpi/mpi_x86_asm.c",
       ]
+      if (is_ios) {
+        sources -= [ "nss/lib/freebl/intel-aes-x86-masm.asm" ]

[Nico, 2015/08/18 15:15:43]

Shouldn't .asm files be ignored automatically on non-Win? Why is this needed for
ios but not other platforms?

[sherouk, 2015/08/18 16:06:23]

No, they are not filtered. This target is only defined on Win, Mac and iOS not
linux. Mac build is not supported by GN yet  

[Nico, 2015/08/18 17:47:05]

There's a main waterfall bot doing GN bots on OS X:
http://build.chromium.org/p/chromium.mac/builders/Mac%20GN%20%28dbg%29/builds...
It builds base_unittests fine.

[sherouk, 2015/08/19 13:14:32]

I was not aware of that bot, Thanks! This bot doesn't build third part nss
because it's not a dependency of base. Do i have to change the condition to be
if(is_ios || is_mac) or i have to remove the condition?

[Nico, 2015/08/19 15:28:05]

Ah, iOS is the only platform we still build NSS on, the rest is on borgingssl by
now, right.. The gyp file seems to unconditionally remove this file on !is_win
(which is already true in this block), so I'd just do this. (i.e. remove the "if
is_ios" line)

In general, looking at the gyp files and doing what's done there where it makes
sense is a good pattern, as the gyp build is known to work.

[sherouk, 2015/08/19 16:50:08]

Done, Thank you!

+      }
     }
 
     if (is_clang) {
       cflags += [
         # nss doesn"t explicitly cast between different enum types.
         "-Wno-conversion",
 
         # nss prefers `a && b || c` over `(a && b) || c`.
         "-Wno-logical-op-parentheses",
 
@@ skipping 11 matching lines @@
     deps = [
       ":nspr",
       "//third_party/sqlite",
     ]
 
     if (is_win && current_cpu == "x86") {
       deps += [ ":nss_static_avx" ]
     }
   }
 }  # Windows/Mac/iOS.