Move Partition Allocator into Chromium base.

base/BUILD.gn

 # Copyright (c) 2013 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.
 
 # HOW TO WRITE CONDITIONALS IN THIS FILE
 # ======================================
 #
 # In many other places, one would write a conditional that expresses all the
 # cases when a source file is used or unused, and then either add or subtract
 # it from the sources list in that case
@@ skipping 1202 matching lines @@
     }
   } else {
     # Remove NaCl stuff.
     sources -= [
       "memory/shared_memory_nacl.cc",
       "os_compat_nacl.cc",
       "os_compat_nacl.h",
       "rand_util_nacl.cc",
       "synchronization/read_write_lock_nacl.cc",
     ]
+
+    # Add stuff that doesn't work in NaCl.
+    sources += [

[gab, 2016/12/05 18:51:48]

Add these to all sources and instead add the exception to the source-= group of
if(is_nacl) on 1147.

[palmer, 2016/12/06 00:58:25]

In an earlier code review, thakis said the general preference to + things rather
than to -= them. (Despite the fact that there is a lot of legacy -= going on.)

I'm agnostic but confused. :)

[gab, 2016/12/06 15:43:21]

Interesting, I'll discuss with him offline. I thought the prefered approach in
the new GN world was to avoid having so many conditions and as such including
files in the default entry and merely removing them with a comment of why where
they don't apply.

I find if(foo) { sources -= [...] } reads better than if (foo) { ... } else {
sources += [...] }

But code search speaks in favor of sources += (295) vs sources -= (92)
https://cs.chromium.org/search/?q=%22sources+%2B%3D%22+file:BUILD.gn&sq=packa...

[gab, 2016/12/06 15:55:06]

Spoke with Nico, preference is now sources += in GN. He'll send a PSA to
chromium-dev introducing this at large later today.

+      # PartitionAlloc uses SpinLock, which doesn't work in NaCl (see below).
+      "allocator/partition_allocator/address_space_randomization.cc",
+      "allocator/partition_allocator/address_space_randomization.h",
+      "allocator/partition_allocator/page_allocator.cc",
+      "allocator/partition_allocator/page_allocator.h",
+      "allocator/partition_allocator/partition_alloc.cc",
+      "allocator/partition_allocator/partition_alloc.h",
+    ]
   }
 
   # SpinLock uses inline assembly that doesn't work on NaCl, and for which there
   # is no code for ARMv6.
   if (!is_nacl && (current_cpu != "arm" || arm_version >= 7)) {
     sources += [
       "synchronization/spin_lock.cc",
       "synchronization/spin_lock.h",
     ]
   }
@@ skipping 545 matching lines @@
     configs += [ "//build/config/compiler:enable_arc" ]
     deps = [
       ":base",
       "//testing/gtest",
     ]
   }
 }
 
 test("base_unittests") {
   sources = [
+    "allocator/partition_allocator/partition_alloc_unittest.cc",
     "allocator/tcmalloc_unittest.cc",
     "android/application_status_listener_unittest.cc",
     "android/content_uri_utils_unittest.cc",
     "android/jni_android_unittest.cc",
     "android/jni_array_unittest.cc",
     "android/jni_string_unittest.cc",
     "android/library_loader/library_prefetcher_unittest.cc",
     "android/path_utils_unittest.cc",
     "android/scoped_java_ref_unittest.cc",
     "android/sys_utils_unittest.cc",
@@ skipping 728 matching lines @@
 }
 
 fuzzer_test("base_json_correctness_fuzzer") {
   sources = [
     "json/correctness_fuzzer.cc",
   ]
   deps = [
     ":base",
   ]
 }