Share precompiled header setup for blink between Windows and Mac.

third_party/WebKit/Source/platform/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/features.gni")
 import("//build/config/ui.gni")
 import("//testing/libfuzzer/fuzzer_test.gni")
 import("//testing/test.gni")
 import("//third_party/WebKit/public/public_features.gni")
 import("//third_party/WebKit/Source/build/scripts/scripts.gni")
@@ skipping 162 matching lines @@
           rebase_path("win/Precompile-platform.h", root_build_dir)
 
       # This is a file that GN will compile with the above header. It will be
       # implicitly added to the sources (potentially multiple times, with one
       # variant for each language used in the target).
       precompiled_source =
           "//third_party/WebKit/Source/platform/win/Precompile-platform.cpp"
 
       # Force include the header.
       cflags = [ "/FI$precompiled_header" ]
+    } else if (is_mac) {
+      precompiled_header =
+          rebase_path("mac/Precompile-platform.h", root_build_dir)
+      precompiled_source =
+          "//third_party/WebKit/Source/platform/mac/Precompile-platform.h"
     }
   }
 }
 
 component("platform") {
   visibility = []  # Allow re-assignment of list.
   visibility = [
     "//third_party/WebKit/*",
     "//url/mojo:url_mojom_origin_blink",
     "//url/mojo:url_mojom_gurl_blink",
@@ skipping 1260 matching lines @@
       "KillRingNone.cpp",
       "fonts/skia/FontCacheSkia.cpp",
       "scroll/ScrollAnimator.cpp",
       "scroll/ScrollAnimator.h",
 
       # Uses LocaleMac instead.
       "text/LocaleICU.cpp",
       "text/LocaleICU.h",
     ]
 
-    configs += [ "//third_party/WebKit/Source:mac_precompiled_headers" ]
     libs = [
       "AppKit.framework",
       "Accelerate.framework",
       "Carbon.framework",
       "Foundation.framework",
     ]
   } else {
     sources -= [
       "geometry/cg/FloatPointCG.cpp",
       "geometry/cg/FloatRectCG.cpp",
@@ skipping 597 matching lines @@
     "//third_party/WebKit/Source:config",
     "//third_party/WebKit/Source:inside_blink",
   ]
 
   deps = [
     ":test_support",
     "//testing/gmock",
     "//testing/gtest",
   ]
 }