Update repo to use dart2js from pkg/compiler.

site/try/build_try.gyp

Index: site/try/build_try.gyp
diff --git a/site/try/build_try.gyp b/site/try/build_try.gyp
index 16388105d993700f9bc083553e408ee2dde9965e..c003fb0e93c64b74afcfe98ef622cda89bda17aa 100644
--- a/site/try/build_try.gyp
+++ b/site/try/build_try.gyp
@@ -75,7 +75,7 @@
             # This dependency is redundant for now, as this directory is
             # implicitly part of the dependencies for dart-sdk/README.
             '<!@(["python", "../../tools/list_files.py", "\\.dart$", '
-                 '"../../sdk/lib/_internal/compiler/samples/jsonify"])',
+                 '"../../pkg/compiler/samples/jsonify"])',
           ],
           'outputs': [
             '<(SHARED_INTERMEDIATE_DIR)/sdk.json',
@@ -87,7 +87,8 @@
 
             '-Dlist_all_libraries=true',
             '-DoutputJson=true',
-            '../../sdk/lib/_internal/compiler/samples/jsonify/jsonify.dart',
+            '--package-root=<(PRODUCT_DIR)/packages/',
+            '../../pkg/compiler/samples/jsonify/jsonify.dart',
             '<(SHARED_INTERMEDIATE_DIR)/sdk.json',
           ],
         },