Split out libplatform into a separate libary

BUILD.gn

Index: BUILD.gn
diff --git a/BUILD.gn b/BUILD.gn
index 18e5ef21ff4c8d99f329ea20ae184a43bf874ad3..02919edf67fe06dcb8bfba5cc960acbbe1dce274 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -14,7 +14,6 @@ v8_enable_verify_heap = false
 v8_interpreted_regexp = false
 v8_object_print = false
 v8_postmortem_support = false
-v8_use_default_platform = true
 v8_use_snapshot = true
 v8_use_external_startup_data = false
 v8_enable_extra_checks = is_debug
@@ -90,11 +89,6 @@ config("features") {
       "V8_I18N_SUPPORT",
     ]
   }
-  if (v8_use_default_platform == true) {
-    defines += [
-      "V8_USE_DEFAULT_PLATFORM",
-    ]
-  }
   if (v8_compress_startup_data == "bz2") {
     defines += [
       "COMPRESS_STARTUP_DATA_BZ2",
@@ -633,13 +627,6 @@ source_set("v8_base") {
     "src/jsregexp-inl.h",
     "src/jsregexp.cc",
     "src/jsregexp.h",
-    # TODO(jochen): move libplatform/ files to their own target.
-    "src/libplatform/default-platform.cc",
-    "src/libplatform/default-platform.h",
-    "src/libplatform/task-queue.cc",
-    "src/libplatform/task-queue.h",
-    "src/libplatform/worker-thread.cc",
-    "src/libplatform/worker-thread.h",
     "src/list-inl.h",
     "src/list.h",
     "src/lithium-allocator-inl.h",
@@ -1077,6 +1064,26 @@ source_set("v8_libbase") {
   # TODO(jochen): Add support for qnx, freebsd, openbsd, netbsd, and solaris.
 }
 
+source_set("v8_libplatform") {

[tfarina, 2014/07/03 18:14:39]

Does this needs visibility?

visibility = ":*"  # Only targets in this file can depend on this.

v8_libbase has this.

If it does not need, then my understanding is that external targets can depend
on this. Is that right?

[jochen (gone - plz use gerrit), 2014/07/03 19:35:20]

yes, external targets can depend on this

+  sources = [
+    "include/libplatform/libplatform.h",
+    "src/libplatform/default-platform.cc",
+    "src/libplatform/default-platform.h",
+    "src/libplatform/task-queue.cc",
+    "src/libplatform/task-queue.h",
+    "src/libplatform/worker-thread.cc",
+    "src/libplatform/worker-thread.h",
+  ]
+
+  configs -= [ "//build/config/compiler:chromium_code" ]
+  configs += [ "//build/config/compiler:no_chromium_code" ]
+  configs += [ ":internal_config", ":features", ":toolchain" ]

[tfarina, 2014/07/03 18:14:39]

does it need also these configs?

[jochen (gone - plz use gerrit), 2014/07/03 19:35:20]

i've modified the configs a bit in a follow-up cl, but essentially, yes, it
does.

+
+  deps = [
+    ":v8_libbase",
+  ]
+}
+
 ###############################################################################
 # Executables
 #
@@ -1095,6 +1102,7 @@ if (current_toolchain == host_toolchain) {
 
     deps = [
       ":v8_base",
+      ":v8_libplatform",
       ":v8_nosnapshot",
     ]