Make chrome/browser and .../ui static libraries.

chrome/browser/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/chrome_build.gni")
 import("//build/config/crypto.gni")
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
 import("//chrome/common/features.gni")
 import("//media/media_options.gni")
@@ skipping 60 matching lines @@
   # If you want to link gnome-keyring directly (use only for unit tests)
   # ADDITIONALLY add this config on top of ":gnome_keyring". pkg-config is a
   # bit slow, so prefer not to run it again. In practice, gnome-keyring's libs
   # are just itself and common gnome ones we link already, so we can get away
   # with additionally just coding the library name here.
   config("gnome_keyring_direct") {
     libs = [ "gnome-keyring" ]
   }
 }
 
-source_set("browser") {
+# Use a static library here because many test binaries depend on this but don't
+# require many files from it. This makes linking more efficient.
+if (is_mac) {
+  # TODO(brettw) bug 618797: On Mac making this target a static_library causes
+  # a crash on startup and the browser_tests all fail. My guess is this is due
+  # to a required static initializer not being brought in.
+  chrome_browser_target_type = "source_set"
+} else {
+  chrome_browser_target_type = "static_library"
+}
+target(chrome_browser_target_type, "browser") {
   configs += [
     "//build/config/compiler:wexit_time_destructors",
     "//build/config:precompiled_headers",
     "//third_party/WebKit/public:debug_devtools",
   ]
   defines = []
   sources = []
   libs = []
   ldflags = []
 
@@ skipping 1261 matching lines @@
   # linking all of the test support.
   source_set("pepper_cdm_test_constants") {
     testonly = true
     visibility = [ "//chrome/*" ]
     sources = [
       "media/pepper_cdm_test_constants.cc",
       "media/pepper_cdm_test_constants.h",
     ]
   }
 }