chrome: Unship snapshot_blob.bin from Win/Mac/Linux

https://chromium.googlesource.com/chromium/src/+/b550792f0f9357f380d501288f368e85d43279b8

fix #548

Auditors: @bridiver, @hferreiro, @ltilve

BUILD.gn

@@ -15,6 +15,7 @@ import("//printing/features/features.gni")
 import("//tools/grit/grit_rule.gni")
 import("//tools/grit/repack.gni")
 import("//ui/base/ui_features.gni")
+import("//tools/v8_context_snapshot/v8_context_snapshot.gni")
 import("//v8/gni/v8.gni")
 import("//third_party/icu/config.gni")
 import("//media/cdm/library_cdm/cdm_paths.gni")
@@ -413,11 +414,14 @@ if (icu_use_data_file) {
 }
 
 if (v8_use_external_startup_data) {
-  electron_framework_sources += [
-    "$root_out_dir/natives_blob.bin",
-    "$root_out_dir/snapshot_blob.bin",
-  ]
+  electron_framework_sources += [ "$root_out_dir/natives_blob.bin" ]
   electron_framework_public_deps += [ "//v8:v8" ]
+  if (use_v8_context_snapshot) {
+    electron_framework_sources += [ "$root_out_dir/v8_context_snapshot.bin" ]
+    electron_framework_public_deps += [ "//tools/v8_context_snapshot" ]
+  } else {
+    electron_framework_sources += [ "$root_out_dir/snapshot_blob.bin" ]
+  }
 }
 
 electron_app_sources = [