[Ignition] Use separate startup data for ignition.

tools/gyp/v8.gyp

Index: tools/gyp/v8.gyp
diff --git a/tools/gyp/v8.gyp b/tools/gyp/v8.gyp
index c418aa737a878e0e48934a6851d1dfdb6c54eea9..53352d66cf33ff47f545732350b1c0441eee43fd 100644
--- a/tools/gyp/v8.gyp
+++ b/tools/gyp/v8.gyp
@@ -353,6 +353,48 @@
               ],
             },
           ],
+          # Extra snapshot blob for ignition. Separate host toolset is not
+          # supported.
+          'conditions': [
+            ['v8_separate_ignition_snapshot==1', {
+              # This is concatenated to the other actions list of
+              # v8_external_snapshot.
+              'actions': [
+                {
+                  'action_name': 'run_mksnapshot (ignition)',
+                  'inputs': [
+                    '<(mksnapshot_exec)',
+                  ],
+                  'variables': {
+                    # TODO: Extract common mksnapshot_flags to a separate
+                    # variable.
+                    'mksnapshot_flags': [
+                      '--ignition',
+                      '--log-snapshot-positions',
+                      '--logfile', '<(INTERMEDIATE_DIR)/snapshot_ignition.log',
+                    ],
+                    'conditions': [
+                      ['v8_random_seed!=0', {
+                        'mksnapshot_flags': ['--random-seed', '<(v8_random_seed)'],
+                      }],
+                      ['v8_vector_stores!=0', {
+                        'mksnapshot_flags': ['--vector-stores'],
+                      }],
+                    ],
+                  },
+                  'outputs': [
+                    '<(PRODUCT_DIR)/snapshot_blob_ignition.bin',
+                  ],
+                  'action': [
+                    '<(mksnapshot_exec)',
+                    '<@(mksnapshot_flags)',
+                    '--startup_blob', '<(PRODUCT_DIR)/snapshot_blob_ignition.bin',
+                    '<(embed_script)',
+                  ],
+                },
+              ],
+            }],
+          ],
         }],
       ],
     },