Build addr2line-pdb from tcmalloc for use in memory-infra symbolization

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.
 
 # This is the root build file for GN. GN will start processing by loading this
 # file, and recursively load all dependencies until all dependencies are either
 # resolved or known not to exist (which will cause the build to fail). So if
 # you add a new build file, there must be some path of dependencies from this
 # file to your new one or GN won't know about it.
 
@@ skipping 736 matching lines @@
     # component builds, due to duplicate symbol definitions.
     if (is_win && is_component_build) {
       deps -= [ "//media/mojo/services:media_service_unittests" ]
     }
 
     if (use_ozone && is_chromeos) {
       deps += [ "//services/ui/display:display_service_unittests" ]
     }
   }
 
+  if (is_win) {
+    deps += [ "//third_party/tcmalloc:addr2line-pdb" ]

[scottmg, 2017/03/03 00:20:24]

There's no such thing as gyp any more so this should go up near line 660, I
think.

[awong, 2017/03/06 18:45:52]

I was told to move it down hear in an earlier review... since I'm a know-nothing
noogler at this point...who should I listen to? :)

[erikchen, 2017/03/06 19:31:17]

I'm the one who asked for this move. This group is called gn_only and the group
above is both_gn_and_gyp. 

+  }
+
   if (is_linux && !is_chromeos && !is_chromecast) {
     # TODO(GYP): Figure out if any of these should be in gn_all
     # and figure out how cross-platform they are
     deps += [
       ":gn_mojo_targets",
       "//chrome/installer/util:strings",
       "//chrome/tools/convert_dict",
       "//components/constrained_window:unit_tests",
       "//components/filesystem:filesystem_service_unittests",
       "//components/leveldb:leveldb_service_unittests",
@@ skipping 341 matching lines @@
   assert(target_name != "")  # Mark as used.
   sources = invoker.actual_sources
   assert(
       sources == invoker.actual_sources,
       "Do not use a platform name in your output directory (found \"$root_build_dir\"). http://crbug.com/548283")
 }
 
 assert_valid_out_dir("_unused") {
   actual_sources = [ "$root_build_dir/foo" ]
 }