Fix import/export annotations for v8 targets that are always static

BUILD.gn

Index: BUILD.gn
diff --git a/BUILD.gn b/BUILD.gn
index ace692a565bf0e6a9cac89e952d9e44082395d1a..83816842fb424de68d9f543b6cdb9dee9963b029 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -2405,6 +2405,10 @@ v8_source_set("fuzzer_support_nocomponent") {
     ":v8_maybe_snapshot",

[jgruber, 2016/10/13 11:36:17]

Just checking - the distinction between fuzzer_support and
fuzzer_support_nocomponent is still needed because of the deps?

[jochen (gone - plz use gerrit), 2016/10/13 12:16:34]

that's mostly because of missing export annotations in the parser. I can fix
that in a follow-up cl

   ]
 
+  if (is_component_build) {
+    defines = [ "BUILDING_V8_SHARED" ]
+  }
+
   public_deps = [
     ":v8_libbase",
     ":v8_libplatform",
@@ -2653,10 +2657,13 @@ v8_executable("v8_parser_shell") {
     "//build/win:default_exe_manifest",
   ]
 
+  defines = []
+
   if (is_component_build) {
     # v8_parser_shell can't be built against a shared library, so we
     # need to depend on the underlying static target in that case.
     deps += [ ":v8_maybe_snapshot" ]
+    defines += [ "BUILDING_V8_SHARED" ]

[Michael Achenbach, 2016/10/13 11:39:30]

Is this reflected in gyp?

[jochen (gone - plz use gerrit), 2016/10/13 12:16:34]

parser shell just doesn't work in gyp/shared_library

   } else {
     deps += [ ":v8" ]
   }
@@ -2744,6 +2751,10 @@ v8_source_set("parser_fuzzer") {
     ":fuzzer_support_nocomponent",
   ]
 
+  if (is_component_build) {
+    defines = [ "BUILDING_V8_SHARED" ]
+  }
+
   configs = [
     ":external_config",
     ":internal_config_base",