bindings: Disable V8 context snapshot feature on cross compile environment

This change can disable the feature on some environments which are
going well, but this is a simple fix to fix the build error on
"32-bit ASAN V8 ARM Builders" bots.


Bug: 760120
Change-Id: I09dc29b61118409baf7f7b538ce376574df175be
Reviewed-on: https://chromium-review.googlesource.com/662962Reviewed-by: Kentaro Hara <haraken@chromium.org>
Reviewed-by: Yuki Shiino <yukishiino@chromium.org>
Commit-Queue: Hitoshi Yoshida <peria@chromium.org>
Cr-Commit-Position: refs/heads/master@{#501533}

tools/v8_context_snapshot/BUILD.gn

@@ -10,6 +10,7 @@
 import("//build/config/c++/c++.gni")
 import("//build/config/chromecast_build.gni")
 import("//build/config/compiler/compiler.gni")
+import("//build/config/v8_target_cpu.gni")
 import("//v8/snapshot_toolchain.gni")
 
 if (is_android) {
@@ -17,7 +18,9 @@ if (is_android) {
 }
 
 declare_args() {
-  use_v8_context_snapshot = !is_chromeos && !is_android && !is_chromecast
+  # TODO(crbug.com/764576): Enable the feature on more environments.
+  use_v8_context_snapshot = !is_chromeos && !is_android && !is_chromecast &&
+                            v8_target_cpu == target_cpu
 }
 
 if (is_android) {