Switch ChromeOS and ChromeCast to use external V8 snapshot files.

BUG=421063

Review URL: https://codereview.chromium.org/1019123002

Cr-Commit-Position: refs/heads/master@{#324052}

build/common.gypi

@@ -1022,9 +1022,8 @@
           'optimize_jni_generation%': 0,
         }],
 
-        # TODO(rmcilroy): Enable v8_use_external_startup_data on ChromeOS
-        # http://crbug.com/421063
-        ['chromecast==0 and chromeos==0 and OS!="ios"', {
+        # TODO(rmcilroy): Remove ios check. http://crbug.com/421063.
+        ['OS!="ios"', {
           'v8_use_external_startup_data%': 1,
         }, {
           'v8_use_external_startup_data%': 0,

chrome/tools/build/chromeos/FILES.cfg

@@ -52,6 +52,14 @@ FILES = [
     'filename': 'installer',
     'buildtype': ['official'],
   },
+  {
+    'filename': 'natives_blob.bin',
+    'buildtype': ['dev', 'official'],
+  },
+  {
+    'filename': 'snapshot_blob.bin',
+    'buildtype': ['dev', 'official'],
+  },
   {
     'filename': 'libffmpegsumo.so',
     'buildtype': ['dev', 'official'],

chromecast/chromecast.gyp

@@ -354,10 +354,15 @@
           'type': 'none',
           'dependencies': [
             '../third_party/icu/icu.gyp:icudata',
+            '../v8/tools/gyp/v8.gyp:v8_external_snapshot',
           ],
           'copies': [{
             'destination': '<(PRODUCT_DIR)/assets',
-            'files': ['<(PRODUCT_DIR)/icudtl.dat'],
+            'files': [
+              '<(PRODUCT_DIR)/icudtl.dat',
+              '<(PRODUCT_DIR)/natives_blob.bin',
+              '<(PRODUCT_DIR)/snapshot_blob.bin',
+            ],
           }],
         },
         {