Fuchsia: Make fuchsia_test use snapshots

runtime/bin/BUILD.gn

Index: runtime/bin/BUILD.gn
diff --git a/runtime/bin/BUILD.gn b/runtime/bin/BUILD.gn
index fa1b461b316ff0d3947c618b7bea80799b948f57..03187f89dc6b1ff55d7fb7f7127855a681b86b19 100644
--- a/runtime/bin/BUILD.gn
+++ b/runtime/bin/BUILD.gn
@@ -212,7 +212,16 @@ static_library("libdart_nosnapshot_with_precompiler") {
   ]
 }
 
-if (!defined(is_fuchsia) || !is_fuchsia) {
+if ((current_toolchain == host_toolchain) ||
+    (!defined(is_fuchsia) || !is_fuchsia)) {
+io_impl_sources_gypi =
+    exec_script("../../tools/gypi_to_gn.py",
+                [ rebase_path("io_impl_sources.gypi") ],
+                "scope",
+                [ "io_impl_sources.gypi" ])
+}
+
+if (current_toolchain == host_toolchain) {
 
 executable("gen_snapshot") {
   configs += ["..:dart_config",
@@ -250,24 +259,6 @@ executable("gen_snapshot") {
   ]
 }
 
-
-source_set("libdart_embedder_noio") {
-  configs += ["..:dart_config",
-              "..:dart_product_config",
-              "..:dart_precompiled_runtime_config"]
-  deps = [
-    "..:libdart",
-    "../vm:libdart_platform",
-  ]
-}
-
-io_impl_sources_gypi =
-    exec_script("../../tools/gypi_to_gn.py",
-                [ rebase_path("io_impl_sources.gypi") ],
-                "scope",
-                [ "io_impl_sources.gypi" ])
-
-
 # A source set for the implementation of 'dart:io' library
 # (without secure sockets) suitable for linking with gen_snapshot.
 source_set("gen_snapshot_dart_io") {
@@ -309,6 +300,20 @@ source_set("gen_snapshot_dart_io") {
   ]
 }
 
+}  # current_toolchain == host_toolchain
+
+source_set("libdart_embedder_noio") {
+  configs += ["..:dart_config",
+              "..:dart_product_config",
+              "..:dart_precompiled_runtime_config"]
+  deps = [
+    "..:libdart",
+    "../vm:libdart_platform",
+  ]
+}
+
+if (!defined(is_fuchsia) || !is_fuchsia) {
+
 # A source set for the implementation of 'dart:io' library
 # (without secure sockets).
 source_set("embedded_dart_io") {
@@ -363,6 +368,81 @@ source_set("embedded_dart_io") {
 }
 }  # !is_fuchsia
 
+
+action("generate_snapshot_bin") {
+  deps = [
+    "../bin:gen_snapshot($host_toolchain)",
+  ]
+
+  vm_isolate_snapshot = "$target_gen_dir/vm_isolate_snapshot.bin"
+  isolate_snapshot = "$target_gen_dir/isolate_snapshot.bin"
+  gen_snapshot_stamp_file = "$target_gen_dir/gen_snapshot.stamp"
+  outputs = [
+    vm_isolate_snapshot,
+    isolate_snapshot,
+    gen_snapshot_stamp_file,
+  ]
+
+  gen_snapshot_dir =
+      get_label_info("../bin:gen_snapshot($host_toolchain)", "root_out_dir")
+
+  script = rebase_path("../tools/create_snapshot_bin.py")
+  args = [
+    "--executable",
+    rebase_path("$gen_snapshot_dir/gen_snapshot"),
+    "--vm_output_bin",
+    rebase_path(vm_isolate_snapshot, root_build_dir),
+    "--output_bin",
+    rebase_path(isolate_snapshot, root_build_dir),
+    "--target_os",
+    current_os,
+    "--timestamp_file",
+    rebase_path(gen_snapshot_stamp_file, root_build_dir),
+  ]
+}
+
+
+action("generate_snapshot_file") {
+  deps = [
+    ":generate_snapshot_bin",
+  ]
+
+  snapshot_in_cc_file = "snapshot_in.cc"
+  inputs = [
+    "../tools/create_snapshot_file.py",
+    snapshot_in_cc_file,
+    "$target_gen_dir/vm_isolate_snapshot.bin",
+    "$target_gen_dir/isolate_snapshot.bin",
+  ]
+  output = "$root_gen_dir/dart_snapshot.cc"
+  outputs = [
+    output,
+  ]
+
+  script = "../tools/create_snapshot_file.py"
+  args = [
+    "--vm_input_bin",
+    rebase_path("$target_gen_dir/vm_isolate_snapshot.bin"),
+    "--input_bin",
+    rebase_path("$target_gen_dir/isolate_snapshot.bin"),
+    "--input_cc",
+    rebase_path(snapshot_in_cc_file),
+    "--output",
+    rebase_path(output),
+  ]
+}
+
+
+source_set("dart_snapshot_cc") {
+  sources = [
+    "$root_gen_dir/dart_snapshot.cc",
+  ]
+
+  deps = [
+    ":generate_snapshot_file",
+  ]
+}
+
 if (defined(is_fuchsia) && is_fuchsia) {
   executable("fuchsia_test") {
     configs += ["..:dart_config",
@@ -379,7 +459,8 @@ if (defined(is_fuchsia) && is_fuchsia) {
     ]
 
     deps = [
-        ":libdart_nosnapshot"
+      ":dart_snapshot_cc",
+      ":libdart_embedder_noio",
     ]
   }
 }