Change option --use_script_snapshot to --use-script-snapshot (easier to type).

utils/compiler/compiler.gyp

Index: utils/compiler/compiler.gyp
===================================================================
--- utils/compiler/compiler.gyp	(revision 17682)
+++ utils/compiler/compiler.gyp	(working copy)
@@ -17,7 +17,6 @@
         {
           'action_name': 'generate_dart2js_snapshot',
           'inputs': [
-            '<(PRODUCT_DIR)/<(EXECUTABLE_PREFIX)gen_snapshot<(EXECUTABLE_SUFFIX)',
             '<(PRODUCT_DIR)/<(EXECUTABLE_PREFIX)dart<(EXECUTABLE_SUFFIX)',
             '../../sdk/lib/_internal/libraries.dart',
             '<!@(["python", "../../tools/list_files.py", "\\.dart$", "../../sdk/lib/_internal/compiler", "../../runtime/lib"])',
@@ -26,13 +25,13 @@
             '<(PRODUCT_DIR)/dart2js.snapshot',
           ],
           'action': [
-            '<(PRODUCT_DIR)/<(EXECUTABLE_PREFIX)gen_snapshot<(EXECUTABLE_SUFFIX)',
+            '<(PRODUCT_DIR)/<(EXECUTABLE_PREFIX)dart<(EXECUTABLE_SUFFIX)',
             # Note: we don't store the snapshot in the location where
             # the dart2js script is looking for it.  The motivation
             # for that is to support an incremental development model
             # for dart2js compiler engineers.  However, we install the
             # snapshot in the proper location when building the SDK.
-            '--script_snapshot=<(PRODUCT_DIR)/dart2js.snapshot',
+            '--generate-script-snapshot=<(PRODUCT_DIR)/dart2js.snapshot',
             '../../sdk/lib/_internal/compiler/implementation/dart2js.dart',
           ],
         },